CWE-120
Allowed-with-ReviewBuffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Abstraction: Base · Status: Incomplete
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.
5452 vulnerabilities reference this CWE, most recent first.
GHSA-36RC-CQ5X-RRPX
Vulnerability from github – Published: 2023-08-29 00:32 – Updated: 2023-12-14 09:30Buffer Overflow vulnerability in O-RAN Software Community ric-plt-lib-rmr v.4.9.0 allows a remote attacker to cause a denial of service via the packet size component.
{
"affected": [],
"aliases": [
"CVE-2023-40998"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-08-28T22:15:10Z",
"severity": "HIGH"
},
"details": "Buffer Overflow vulnerability in O-RAN Software Community ric-plt-lib-rmr v.4.9.0 allows a remote attacker to cause a denial of service via the packet size component.",
"id": "GHSA-36rc-cq5x-rrpx",
"modified": "2023-12-14T09:30:18Z",
"published": "2023-08-29T00:32:04Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-40998"
},
{
"type": "WEB",
"url": "https://jira.o-ran-sc.org/browse/RIC-989"
},
{
"type": "WEB",
"url": "https://www.trendmicro.com/en_us/research/23/l/the-current-state-of-open-ran-security.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-36XJ-GCR2-CGRF
Vulnerability from github – Published: 2024-01-24 18:31 – Updated: 2024-09-05 21:31Buffer Overflow vulnerability in the nomath() function in Mathtex v.1.05 and before allows a remote attacker to cause a denial of service via a crafted string in the application URL.
{
"affected": [],
"aliases": [
"CVE-2023-51888"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-01-24T18:15:08Z",
"severity": "HIGH"
},
"details": "Buffer Overflow vulnerability in the nomath() function in Mathtex v.1.05 and before allows a remote attacker to cause a denial of service via a crafted string in the application URL.",
"id": "GHSA-36xj-gcr2-cgrf",
"modified": "2024-09-05T21:31:33Z",
"published": "2024-01-24T18:31:01Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-51888"
},
{
"type": "WEB",
"url": "https://blog.yulun.ac.cn/posts/2023/fuzzing-mathtex"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-3724-4MMC-J59X
Vulnerability from github – Published: 2021-12-08 00:00 – Updated: 2021-12-09 00:01NoMachine Enterprise Desktop is affected by Buffer Overflow. IOCTL Handler 0x22001B in the NoMachine Enterprise Desktop above 4.0.346 and below 7.7.4 allow local attackers to execute arbitrary code in kernel mode or cause a denial of service (memory corruption and OS crash) via specially crafted I/O Request Packet.
{
"affected": [],
"aliases": [
"CVE-2021-42976"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-12-07T20:15:00Z",
"severity": "HIGH"
},
"details": "NoMachine Enterprise Desktop is affected by Buffer Overflow. IOCTL Handler 0x22001B in the NoMachine Enterprise Desktop above 4.0.346 and below 7.7.4 allow local attackers to execute arbitrary code in kernel mode or cause a denial of service (memory corruption and OS crash) via specially crafted I/O Request Packet.",
"id": "GHSA-3724-4mmc-j59x",
"modified": "2021-12-09T00:01:23Z",
"published": "2021-12-08T00:00:59Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-42976"
},
{
"type": "WEB",
"url": "https://www.sentinelone.com/labs/usb-over-ethernet-multiple-privilege-escalation-vulnerabilities-in-aws-and-other-major-cloud-services"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-373G-HG3V-QF78
Vulnerability from github – Published: 2024-08-06 21:30 – Updated: 2024-08-07 00:30Heap buffer overflow in Layout in Google Chrome prior to 127.0.6533.99 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)
{
"affected": [],
"aliases": [
"CVE-2024-7534"
],
"database_specific": {
"cwe_ids": [
"CWE-120",
"CWE-122",
"CWE-787"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-08-06T21:16:04Z",
"severity": "HIGH"
},
"details": "Heap buffer overflow in Layout in Google Chrome prior to 127.0.6533.99 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)",
"id": "GHSA-373g-hg3v-qf78",
"modified": "2024-08-07T00:30:47Z",
"published": "2024-08-06T21:30:48Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-7534"
},
{
"type": "WEB",
"url": "https://chromereleases.googleblog.com/2024/08/stable-channel-update-for-desktop.html"
},
{
"type": "WEB",
"url": "https://issues.chromium.org/issues/352467338"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-3744-988X-MQXH
Vulnerability from github – Published: 2023-11-14 21:30 – Updated: 2023-11-14 21:30Buffer copy without checking size of input ('Classic Buffer Overflow') vulnerability in cgi component in Synology SSL VPN Client before 1.4.7-0687 allows local users to conduct denial-of-service attacks via unspecified vectors.
{
"affected": [],
"aliases": [
"CVE-2023-5748"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-11-07T04:24:19Z",
"severity": "MODERATE"
},
"details": "Buffer copy without checking size of input (\u0027Classic Buffer Overflow\u0027) vulnerability in cgi component in Synology SSL VPN Client before 1.4.7-0687 allows local users to conduct denial-of-service attacks via unspecified vectors.",
"id": "GHSA-3744-988x-mqxh",
"modified": "2023-11-14T21:30:51Z",
"published": "2023-11-14T21:30:51Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-5748"
},
{
"type": "WEB",
"url": "https://www.synology.com/en-global/security/advisory/Synology_SA_23_12"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-3745-9RXM-69M7
Vulnerability from github – Published: 2026-02-11 21:30 – Updated: 2026-02-11 21:30SpotFTP 3.0.0.0 contains a denial of service vulnerability in the registration name input field that allows attackers to crash the application. Attackers can generate a 1000-character buffer payload and paste it into the 'Name' field to trigger an application crash.
{
"affected": [],
"aliases": [
"CVE-2020-37209"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-02-11T21:16:16Z",
"severity": "MODERATE"
},
"details": "SpotFTP 3.0.0.0 contains a denial of service vulnerability in the registration name input field that allows attackers to crash the application. Attackers can generate a 1000-character buffer payload and paste it into the \u0027Name\u0027 field to trigger an application crash.",
"id": "GHSA-3745-9rxm-69m7",
"modified": "2026-02-11T21:30:42Z",
"published": "2026-02-11T21:30:42Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-37209"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/47868"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/spotftp-ftp-password-recovery-name-denial-of-service"
},
{
"type": "WEB",
"url": "http://www.nsauditor.com"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-375C-626V-C7M7
Vulnerability from github – Published: 2022-05-24 17:35 – Updated: 2022-05-24 17:35A heap overflow vulnerability exists in Pixar OpenUSD 20.05 when the software parses compressed sections in binary USD files. A specially crafted USDC file format path jumps decompression heap overflow in a way path jumps are processed. To trigger this vulnerability, the victim needs to open an attacker-provided malformed file.
{
"affected": [],
"aliases": [
"CVE-2020-13493"
],
"database_specific": {
"cwe_ids": [
"CWE-120",
"CWE-787"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-12-02T18:15:00Z",
"severity": "HIGH"
},
"details": "A heap overflow vulnerability exists in Pixar OpenUSD 20.05 when the software parses compressed sections in binary USD files. A specially crafted USDC file format path jumps decompression heap overflow in a way path jumps are processed. To trigger this vulnerability, the victim needs to open an attacker-provided malformed file.",
"id": "GHSA-375c-626v-c7m7",
"modified": "2022-05-24T17:35:06Z",
"published": "2022-05-24T17:35:06Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-13493"
},
{
"type": "WEB",
"url": "https://talosintelligence.com/vulnerability_reports/TALOS-2020-1094"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-375G-39JQ-VQ7M
Vulnerability from github – Published: 2024-02-21 00:09 – Updated: 2025-01-14 15:59Summary
Ever since https://github.com/agronholm/cbor2/pull/204 (or specifically https://github.com/agronholm/cbor2/commit/387755eacf0be35591a478d3c67fe10618a6d542) was merged, I can create a reproducible crash when running the snippet under PoC on a current Debian bullseye aarm64 on a Raspberry Pi 3 (I was not able to reproduce this on my x86_64 Laptop with Python 3.11; I suspect because there is enough memory to allocate still)
Details
PoC
import json
import concurrent.futures
import cbor2
def test():
obj = "x" * 131128
cbor_enc = cbor2.dumps(obj)
return cbor2.loads(cbor_enc)
with concurrent.futures.ProcessPoolExecutor() as executor:
future = executor.submit(test)
print(future.result())
malloc(): unsorted double linked list corrupted
Traceback (most recent call last):
File "test.py", line 14, in <module>
print(future.result())
File "/usr/lib/python3.9/concurrent/futures/_base.py", line 440, in result
return self.__get_result()
File "/usr/lib/python3.9/concurrent/futures/_base.py", line 389, in __get_result
raise self._exception
concurrent.futures.process.BrokenProcessPool: A process in the process pool was terminated abruptly while the future was running or pending.
If one calls it without the indirection via the pool executor, a SystemError is shown that hides the buffer overflow.
import json
import cbor2
def test():
obj = "x" * 131128
cbor_enc = cbor2.dumps(obj)
return cbor2.loads(cbor_enc)
print(test())
Traceback (most recent call last):
File "test.py", line 12, in <module>
print(test())
File "test.py", line 9, in test
return cbor2.loads(cbor_enc)
SystemError: <built-in function loads> returned NULL without setting an error
Impact
An attacker can crash a service using cbor2 to parse a CBOR binary by sending a long enough object.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "cbor2"
},
"ranges": [
{
"events": [
{
"introduced": "5.5.1"
},
{
"fixed": "5.6.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-26134"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": true,
"github_reviewed_at": "2024-02-21T00:09:03Z",
"nvd_published_at": "2024-02-19T23:15:07Z",
"severity": "HIGH"
},
"details": "### Summary\nEver since https://github.com/agronholm/cbor2/pull/204 (or specifically https://github.com/agronholm/cbor2/commit/387755eacf0be35591a478d3c67fe10618a6d542) was merged, I can create a reproducible crash when running the snippet under PoC on a current Debian bullseye aarm64 on a Raspberry Pi 3 (I was **not** able to reproduce this on my x86_64 Laptop with Python 3.11; I suspect because there is enough memory to allocate still)\n\n## Details\n\n\n### PoC\n```py\nimport json\nimport concurrent.futures\nimport cbor2\n\ndef test():\n obj = \"x\" * 131128\n cbor_enc = cbor2.dumps(obj)\n return cbor2.loads(cbor_enc)\n\nwith concurrent.futures.ProcessPoolExecutor() as executor:\n future = executor.submit(test)\n print(future.result())\n```\n\n```\nmalloc(): unsorted double linked list corrupted\nTraceback (most recent call last):\n File \"test.py\", line 14, in \u003cmodule\u003e\n print(future.result())\n File \"/usr/lib/python3.9/concurrent/futures/_base.py\", line 440, in result\n return self.__get_result()\n File \"/usr/lib/python3.9/concurrent/futures/_base.py\", line 389, in __get_result\n raise self._exception\nconcurrent.futures.process.BrokenProcessPool: A process in the process pool was terminated abruptly while the future was running or pending.\n```\n\nIf one calls it without the indirection via the pool executor, a SystemError is shown that hides the buffer overflow.\n\n```py\nimport json\nimport cbor2\n\ndef test():\n obj = \"x\" * 131128\n cbor_enc = cbor2.dumps(obj)\n return cbor2.loads(cbor_enc)\n\nprint(test())\n```\n\n```\nTraceback (most recent call last):\n File \"test.py\", line 12, in \u003cmodule\u003e\n print(test())\n File \"test.py\", line 9, in test\n return cbor2.loads(cbor_enc)\nSystemError: \u003cbuilt-in function loads\u003e returned NULL without setting an error\n```\n\n### Impact\nAn attacker can crash a service using cbor2 to parse a CBOR binary by sending a long enough object.",
"id": "GHSA-375g-39jq-vq7m",
"modified": "2025-01-14T15:59:39Z",
"published": "2024-02-21T00:09:03Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/agronholm/cbor2/security/advisories/GHSA-375g-39jq-vq7m"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-26134"
},
{
"type": "WEB",
"url": "https://github.com/agronholm/cbor2/pull/204"
},
{
"type": "WEB",
"url": "https://github.com/agronholm/cbor2/commit/387755eacf0be35591a478d3c67fe10618a6d542"
},
{
"type": "WEB",
"url": "https://github.com/agronholm/cbor2/commit/4de6991ba29bf2290d7b9d83525eda7d021873df"
},
{
"type": "PACKAGE",
"url": "https://github.com/agronholm/cbor2"
},
{
"type": "WEB",
"url": "https://github.com/agronholm/cbor2/releases/tag/5.6.2"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/cbor2/PYSEC-2024-155.yaml"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BT42VXZMMMCSSHMA65KKPOZCXJEYHNR5"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GX524ZG2XJWFV37UQKQ4LWIH4UICSGEQ"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PWC3VU6YV6EXKCSX5GTKWLBZIDIJNQJY"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
],
"summary": "Potential buffer overflow in CBOR2 decoder"
}
GHSA-37F5-2Q74-7WVC
Vulnerability from github – Published: 2022-05-24 19:03 – Updated: 2024-02-27 21:31A buffer overflow vulnerability exists in Windows File Resource Profiles in 9.X allows a remote authenticated user with privileges to browse SMB shares to execute arbitrary code as the root user. As of version 9.1R3, this permission is not enabled by default.
{
"affected": [],
"aliases": [
"CVE-2021-22908"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-05-27T12:15:00Z",
"severity": "HIGH"
},
"details": "A buffer overflow vulnerability exists in Windows File Resource Profiles in 9.X allows a remote authenticated user with privileges to browse SMB shares to execute arbitrary code as the root user. As of version 9.1R3, this permission is not enabled by default.",
"id": "GHSA-37f5-2q74-7wvc",
"modified": "2024-02-27T21:31:23Z",
"published": "2022-05-24T19:03:30Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-22908"
},
{
"type": "WEB",
"url": "https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44800"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-37Q6-VW96-Q6Q8
Vulnerability from github – Published: 2022-05-24 17:36 – Updated: 2022-05-24 17:36An issue was discovered in Contiki through 3.0 and Contiki-NG through 4.5. The code for parsing Type A domain name answers in ip64-dns64.c doesn't verify whether the address in the answer's length is sane. Therefore, when copying an address of an arbitrary length, a buffer overflow can occur. This bug can be exploited whenever NAT64 is enabled.
{
"affected": [],
"aliases": [
"CVE-2020-24336"
],
"database_specific": {
"cwe_ids": [
"CWE-120"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-12-11T23:15:00Z",
"severity": "CRITICAL"
},
"details": "An issue was discovered in Contiki through 3.0 and Contiki-NG through 4.5. The code for parsing Type A domain name answers in ip64-dns64.c doesn\u0027t verify whether the address in the answer\u0027s length is sane. Therefore, when copying an address of an arbitrary length, a buffer overflow can occur. This bug can be exploited whenever NAT64 is enabled.",
"id": "GHSA-37q6-vw96-q6q8",
"modified": "2022-05-24T17:36:11Z",
"published": "2022-05-24T17:36:11Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-24336"
},
{
"type": "WEB",
"url": "https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01"
},
{
"type": "WEB",
"url": "https://www.kb.cert.org/vuls/id/815128"
}
],
"schema_version": "1.4.0",
"severity": []
}
Mitigation MIT-3
Strategy: Language Selection
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer.
- Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
Mitigation MIT-4.1
Strategy: Libraries or Frameworks
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- Examples include the Safe C String Library (SafeStr) by Messier and Viega [REF-57], and the Strsafe.h library from Microsoft [REF-56]. These libraries provide safer versions of overflow-prone string-handling functions.
Mitigation MIT-10
Strategy: Environment Hardening
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
- D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
Mitigation MIT-9
- Consider adhering to the following rules when allocating and managing an application's memory:
- Double check that your buffer is as large as you specify.
- When using functions that accept a number of bytes to copy, such as strncpy(), be aware that if the destination buffer size is equal to the source buffer size, it may not NULL-terminate the string.
- Check buffer boundaries if accessing the buffer in a loop and make sure there is no danger of writing past the allocated space.
- If necessary, truncate all input strings to a reasonable length before passing them to the copy and concatenation functions.
Mitigation MIT-5
Strategy: Input Validation
- Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
Mitigation MIT-15
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
Mitigation MIT-11
Strategy: Environment Hardening
- Run or compile the software using features or extensions that randomly arrange the positions of a program's executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
- Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as "rebasing" (for Windows) and "prelinking" (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
- For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].
Mitigation MIT-12
Strategy: Environment Hardening
- Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX [REF-60] [REF-61]. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment.
- For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND [REF-1336].
Mitigation
Most mitigating technologies at the compiler or OS level to date address only a subset of buffer overflow problems and rarely provide complete protection against even that subset. It is good practice to implement strategies to increase the workload of an attacker, such as leaving the attacker to guess an unknown value that changes every program execution.
Mitigation MIT-13
Replace unbounded copy functions with analogous functions that support length arguments, such as strcpy with strncpy. Create these if they are not available.
Mitigation MIT-21
Strategy: Enforcement by Conversion
When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
Mitigation MIT-17
Strategy: Environment Hardening
Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
Mitigation MIT-22
Strategy: Sandbox or Jail
- Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
- OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
- This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
- Be careful to avoid CWE-243 and other weaknesses related to jails.
CAPEC-10: Buffer Overflow via Environment Variables
This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the adversary finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
CAPEC-100: Overflow Buffers
Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an adversary. As a consequence, an adversary is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the adversaries' choice.
CAPEC-14: Client-side Injection-induced Buffer Overflow
This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service. This hostile service is created to deliver the correct content to the client software. For example, if the client-side application is a browser, the service will host a webpage that the browser loads.
CAPEC-24: Filter Failure through Buffer Overflow
In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
CAPEC-42: MIME Conversion
An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.
CAPEC-44: Overflow Binary Resource File
An attack of this type exploits a buffer overflow vulnerability in the handling of binary resources. Binary resources may include music files like MP3, image files like JPEG files, and any other binary file. These attacks may pass unnoticed to the client machine through normal usage of files, such as a browser loading a seemingly innocent JPEG file. This can allow the adversary access to the execution stack and execute arbitrary code in the target process.
CAPEC-45: Buffer Overflow via Symbolic Links
This type of attack leverages the use of symbolic links to cause buffer overflows. An adversary can try to create or manipulate a symbolic link file such that its contents result in out of bounds data. When the target software processes the symbolic link file, it could potentially overflow internal buffers with insufficient bounds checking.
CAPEC-46: Overflow Variables and Tags
This type of attack leverages the use of tags or variables from a formatted configuration data to cause buffer overflow. The adversary crafts a malicious HTML page or configuration file that includes oversized strings, thus causing an overflow.
CAPEC-47: Buffer Overflow via Parameter Expansion
In this attack, the target software is given input that the adversary knows will be modified and expanded in size during processing. This attack relies on the target software failing to anticipate that the expanded data may exceed some internal limit, thereby creating a buffer overflow.
CAPEC-67: String Format Overflow in syslog()
This attack targets applications and software that uses the syslog() function insecurely. If an application does not explicitely use a format string parameter in a call to syslog(), user input can be placed in the format string parameter leading to a format string injection attack. Adversaries can then inject malicious format string commands into the function call leading to a buffer overflow. There are many reported software vulnerabilities with the root cause being a misuse of the syslog() function.
CAPEC-8: Buffer Overflow in an API Call
This attack targets libraries or shared code modules which are vulnerable to buffer overflow attacks. An adversary who has knowledge of known vulnerable libraries or shared code can easily target software that makes use of these libraries. All clients that make use of the code library thus become vulnerable by association. This has a very broad effect on security across a system, usually affecting more than one software process.
CAPEC-9: Buffer Overflow in Local Command-Line Utilities
This attack targets command-line utilities available in a number of shells. An adversary can leverage a vulnerability found in a command-line utility to escalate privilege to root.
CAPEC-92: Forced Integer Overflow
This attack forces an integer variable to go out of range. The integer variable is often used as an offset such as size of memory allocation or similarly. The attacker would typically control the value of such variable and try to get it out of range. For instance the integer in question is incremented past the maximum possible value, it may wrap to become a very small, or negative number, therefore providing a very incorrect value which can lead to unexpected behavior. At worst the attacker can execute arbitrary code.