Common Weakness Enumeration
CWE-122
AllowedHeap-based Buffer Overflow
Abstraction: Variant · Status: Draft
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
4106 vulnerabilities reference this CWE, most recent first.
GHSA-CQC3-WP4C-VRCW
Vulnerability from github – Published: 2024-02-13 18:38 – Updated: 2024-02-13 18:38
VLAI
Details
Microsoft WDAC OLE DB provider for SQL Server Remote Code Execution Vulnerability
Severity
8.8 (High)
{
"affected": [],
"aliases": [
"CVE-2024-21360"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-02-13T18:15:52Z",
"severity": "HIGH"
},
"details": "Microsoft WDAC OLE DB provider for SQL Server Remote Code Execution Vulnerability",
"id": "GHSA-cqc3-wp4c-vrcw",
"modified": "2024-02-13T18:38:23Z",
"published": "2024-02-13T18:38:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-21360"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21360"
}
],
"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-CQJV-C8HW-93X7
Vulnerability from github – Published: 2026-06-09 18:30 – Updated: 2026-06-09 18:30
VLAI
Details
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Severity
7.8 (High)
{
"affected": [],
"aliases": [
"CVE-2026-45638"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-09T17:17:30Z",
"severity": "HIGH"
},
"details": "Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.",
"id": "GHSA-cqjv-c8hw-93x7",
"modified": "2026-06-09T18:30:52Z",
"published": "2026-06-09T18:30:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45638"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45638"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-CQX9-3CPJ-RRQP
Vulnerability from github – Published: 2026-03-19 21:30 – Updated: 2026-03-26 18:31
VLAI
Details
Heap-based buffer overflow in the KCAPI ECC code path of wc_ecc_import_x963_ex() in wolfSSL wolfcrypt allows a remote attacker to write attacker-controlled data past the bounds of the pubkey_raw buffer via a crafted oversized EC public key point. The WOLFSSL_KCAPI_ECC code path copies the input to key->pubkey_raw (132 bytes) using XMEMCPY without a bounds check, unlike the ATECC code path which includes a length validation. This can be triggered during TLS key exchange when a malicious peer sends a crafted ECPoint in ServerKeyExchange.
Severity
{
"affected": [],
"aliases": [
"CVE-2026-4395"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-03-19T21:17:13Z",
"severity": "LOW"
},
"details": "Heap-based buffer overflow in the KCAPI ECC code path of wc_ecc_import_x963_ex() in wolfSSL wolfcrypt allows a remote attacker to write attacker-controlled data past the bounds of the pubkey_raw buffer via a crafted oversized EC public key point. The WOLFSSL_KCAPI_ECC code path copies the input to key-\u003epubkey_raw (132 bytes) using XMEMCPY without a bounds check, unlike the ATECC code path which includes a length validation. This can be triggered during TLS key exchange when a malicious peer sends a crafted ECPoint in ServerKeyExchange.",
"id": "GHSA-cqx9-3cpj-rrqp",
"modified": "2026-03-26T18:31:27Z",
"published": "2026-03-19T21:30:25Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-4395"
},
{
"type": "WEB",
"url": "https://github.com/wolfSSL/wolfssl/pull/9988"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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:Y/R:U/V:D/RE:L/U:Amber",
"type": "CVSS_V4"
}
]
}
GHSA-CR67-PVMX-2PP2
Vulnerability from github – Published: 2026-04-13 19:33 – Updated: 2026-04-15 20:56
VLAI
Summary
ImageMagick has a heap-Buffer-Overflow write of a single zero byte when parsing xml.
Details
When Magick parses an XML file it is possible that a single zero byte is written out of the bounds.
Severity
5.3 (Medium)
{
"affected": [
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-AnyCPU"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-HDRI-AnyCPU"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-HDRI-OpenMP-arm64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-HDRI-arm64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-HDRI-x64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-HDRI-x86"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-OpenMP-arm64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-OpenMP-x64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-arm64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-x64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q16-x86"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q8-AnyCPU"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q8-OpenMP-arm64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q8-OpenMP-x64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q8-arm64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q8-x64"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "Magick.NET-Q8-x86"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "14.12.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-33899"
],
"database_specific": {
"cwe_ids": [
"CWE-122",
"CWE-191"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-13T19:33:00Z",
"nvd_published_at": "2026-04-13T21:16:25Z",
"severity": "MODERATE"
},
"details": "When `Magick` parses an XML file it is possible that a single zero byte is written out of the bounds.",
"id": "GHSA-cr67-pvmx-2pp2",
"modified": "2026-04-15T20:56:24Z",
"published": "2026-04-13T19:33:00Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/ImageMagick/ImageMagick/security/advisories/GHSA-cr67-pvmx-2pp2"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33899"
},
{
"type": "WEB",
"url": "https://github.com/ImageMagick/ImageMagick/commit/ae679e2fd19ec656bfab9f822ae4cf06bf91604d"
},
{
"type": "PACKAGE",
"url": "https://github.com/ImageMagick/ImageMagick"
},
{
"type": "WEB",
"url": "https://github.com/ImageMagick/ImageMagick/releases/tag/7.1.2-19"
},
{
"type": "WEB",
"url": "https://github.com/dlemstra/Magick.NET/releases/tag/14.12.0"
}
],
"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:L",
"type": "CVSS_V3"
}
],
"summary": "ImageMagick has a heap-Buffer-Overflow write of a single zero byte when parsing xml."
}
GHSA-CRJ8-FMHJ-6R4H
Vulnerability from github – Published: 2026-06-09 18:30 – Updated: 2026-06-09 18:30
VLAI
Details
Heap-based buffer overflow in Remote Desktop Client allows an unauthorized attacker to execute code over a network.
Severity
7.5 (High)
{
"affected": [],
"aliases": [
"CVE-2026-44799"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-09T17:17:15Z",
"severity": "HIGH"
},
"details": "Heap-based buffer overflow in Remote Desktop Client allows an unauthorized attacker to execute code over a network.",
"id": "GHSA-crj8-fmhj-6r4h",
"modified": "2026-06-09T18:30:46Z",
"published": "2026-06-09T18:30:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44799"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-44799"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-CVC6-XW8J-M5H3
Vulnerability from github – Published: 2022-05-24 16:58 – Updated: 2024-04-04 02:14
VLAI
Details
A specifically crafted jpeg2000 file embedded in a PDF file can lead to a heap corruption when opening a PDF document in NitroPDF 12.12.1.522. With careful memory manipulation, this can lead to arbitrary code execution. In order to trigger this vulnerability, the victim would need to open the malicious file.
Severity
7.8 (High)
{
"affected": [],
"aliases": [
"CVE-2019-5046"
],
"database_specific": {
"cwe_ids": [
"CWE-122",
"CWE-787"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-10-09T21:15:00Z",
"severity": "HIGH"
},
"details": "A specifically crafted jpeg2000 file embedded in a PDF file can lead to a heap corruption when opening a PDF document in NitroPDF 12.12.1.522. With careful memory manipulation, this can lead to arbitrary code execution. In order to trigger this vulnerability, the victim would need to open the malicious file.",
"id": "GHSA-cvc6-xw8j-m5h3",
"modified": "2024-04-04T02:14:08Z",
"published": "2022-05-24T16:58:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-5046"
},
{
"type": "WEB",
"url": "https://talosintelligence.com/vulnerability_reports/TALOS-2019-0815"
}
],
"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-CVHQ-Q927-GR5Q
Vulnerability from github – Published: 2025-12-11 21:31 – Updated: 2025-12-11 21:31
VLAI
Details
In NrmmDecoder::DecodeSORTransparentContext of cn_NrmmDecoder.cpp, there is a possible out of bounds write due to a heap buffer overflow. This could lead to remote (proximal/adjacent) escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
Severity
8.0 (High)
{
"affected": [],
"aliases": [
"CVE-2025-36923"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-11T20:15:56Z",
"severity": "HIGH"
},
"details": "In NrmmDecoder::DecodeSORTransparentContext of cn_NrmmDecoder.cpp, there is a possible out of bounds write due to a heap buffer overflow. This could lead to remote (proximal/adjacent) escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.",
"id": "GHSA-cvhq-q927-gr5q",
"modified": "2025-12-11T21:31:33Z",
"published": "2025-12-11T21:31:33Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-36923"
},
{
"type": "WEB",
"url": "https://source.android.com/security/bulletin/pixel/2025-12-01"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-CVM5-7WP7-VFJV
Vulnerability from github – Published: 2022-08-02 00:00 – Updated: 2022-08-05 00:00
VLAI
Details
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.0101.
Severity
7.8 (High)
{
"affected": [],
"aliases": [
"CVE-2022-2571"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-08-01T15:15:00Z",
"severity": "HIGH"
},
"details": "Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.0101.",
"id": "GHSA-cvm5-7wp7-vfjv",
"modified": "2022-08-05T00:00:21Z",
"published": "2022-08-02T00:00:25Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-2571"
},
{
"type": "WEB",
"url": "https://github.com/vim/vim/commit/a6f9e300161f4cb54713da22f65b261595e8e614"
},
{
"type": "WEB",
"url": "https://huntr.dev/bounties/2e5a1dc4-2dfb-4e5f-8c70-e1ede21f3571"
}
],
"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-CVPH-C7FW-4MJC
Vulnerability from github – Published: 2024-06-26 21:32 – Updated: 2024-08-12 21:31
VLAI
Details
Heap Buffer Overflow vulnerability in Libde265 v1.0.15 allows attackers to crash the application via crafted payload to __interceptor_memcpy function.
Severity
6.5 (Medium)
{
"affected": [],
"aliases": [
"CVE-2024-38950"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-06-26T20:15:16Z",
"severity": "MODERATE"
},
"details": "Heap Buffer Overflow vulnerability in Libde265 v1.0.15 allows attackers to crash the application via crafted payload to __interceptor_memcpy function.",
"id": "GHSA-cvph-c7fw-4mjc",
"modified": "2024-08-12T21:31:32Z",
"published": "2024-06-26T21:32:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-38950"
},
{
"type": "WEB",
"url": "https://github.com/strukturag/libde265/issues/460"
},
{
"type": "WEB",
"url": "https://github.com/zhangteng0526/CVE-information/blob/main/CVE-2024-38950"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-CVQG-H5HX-C2M4
Vulnerability from github – Published: 2024-05-03 03:30 – Updated: 2025-11-04 21:31
VLAI
Details
GStreamer PGS File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer. Interaction with this library is required to exploit this vulnerability but attack vectors may vary depending on the implementation.
The specific flaw exists within the parsing of PGS subtitle files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-20994.
Severity
8.8 (High)
{
"affected": [],
"aliases": [
"CVE-2023-37328"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-03T02:15:43Z",
"severity": "HIGH"
},
"details": "GStreamer PGS File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer. Interaction with this library is required to exploit this vulnerability but attack vectors may vary depending on the implementation.\n\nThe specific flaw exists within the parsing of PGS subtitle files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-20994.",
"id": "GHSA-cvqg-h5hx-c2m4",
"modified": "2025-11-04T21:31:29Z",
"published": "2024-05-03T03:30:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-37328"
},
{
"type": "WEB",
"url": "https://gstreamer.freedesktop.org/security/sa-2023-0003.html"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IGQEFZ6ZB3C2XU4JQD3IAFMQIN456W2D"
},
{
"type": "WEB",
"url": "https://www.zerodayinitiative.com/advisories/ZDI-23-901"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Mitigation
Pre-design: Use a language or compiler that performs automatic bounds checking.
Mitigation
Architecture and Design
Use an abstraction library to abstract away risky APIs. Not a complete solution.
Mitigation MIT-10
Operation
Build and Compilation
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-11
Operation
Build and Compilation
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
Implementation
Implement and perform bounds checking on input.
Mitigation
Implementation
Strategy: Libraries or Frameworks
Do not use dangerous functions such as gets. Look for their safe equivalent, which checks for the boundary.
Mitigation
Operation
Use OS-level preventative functionality. This is not a complete solution, but it provides some defense in depth.
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.