Vulnerability-Lookup

CNVD-2021-34746

Vulnerability from cnvd - Published: 2021-05-15

Title

Linux kernel信息泄露漏洞（CNVD-2021-34746）

Description

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。KVM是其中的一个基于内核的虚拟机。 Linux kernel 存在安全漏洞，本地攻击者可利用该漏洞可以通过Linux内核的BPF读取内存片段，以获取敏感信息。

Severity

低

Patch Name

Linux kernel信息泄露漏洞（CNVD-2021-34746）的补丁

Patch Description

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。KVM是其中的一个基于内核的虚拟机。 Linux kernel 存在安全漏洞，本地攻击者可利用该漏洞可以通过Linux内核的BPF读取内存片段，以获取敏感信息。目前，供应商发布了安全公告及相关补丁信息，修复了此漏洞。

Formal description

目前厂商已发布升级补丁以修复漏洞，补丁获取链接： https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/patch/?id=b9b34ddbe2076ade359cd5ce7537d5ed019e9807

Reference

https://vigilance.fr/vulnerability/Linux-kernel-information-disclosure-via-BPF-35231

Impacted products

Name
Linux Linux kernel <=5.12.1

Show details on source website

JSON

To clipboard

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  "cves": {
    "cve": {
      "cveNumber": "CVE-2021-31829"
    }
  },
  "description": "Linux kernel\u662f\u7f8e\u56fdLinux\u57fa\u91d1\u4f1a\u7684\u5f00\u6e90\u64cd\u4f5c\u7cfb\u7edfLinux\u6240\u4f7f\u7528\u7684\u5185\u6838\u3002KVM\u662f\u5176\u4e2d\u7684\u4e00\u4e2a\u57fa\u4e8e\u5185\u6838\u7684\u865a\u62df\u673a\u3002\n\nLinux kernel \u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u672c\u5730\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u53ef\u4ee5\u901a\u8fc7Linux\u5185\u6838\u7684BPF\u8bfb\u53d6\u5185\u5b58\u7247\u6bb5\uff0c\u4ee5\u83b7\u53d6\u654f\u611f\u4fe1\u606f\u3002",
  "formalWay": "\u76ee\u524d\u5382\u5546\u5df2\u53d1\u5e03\u5347\u7ea7\u8865\u4e01\u4ee5\u4fee\u590d\u6f0f\u6d1e\uff0c\u8865\u4e01\u83b7\u53d6\u94fe\u63a5\uff1a\r\nhttps://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/patch/?id=b9b34ddbe2076ade359cd5ce7537d5ed019e9807",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2021-34746",
  "openTime": "2021-05-15",
  "patchDescription": "Linux kernel\u662f\u7f8e\u56fdLinux\u57fa\u91d1\u4f1a\u7684\u5f00\u6e90\u64cd\u4f5c\u7cfb\u7edfLinux\u6240\u4f7f\u7528\u7684\u5185\u6838\u3002KVM\u662f\u5176\u4e2d\u7684\u4e00\u4e2a\u57fa\u4e8e\u5185\u6838\u7684\u865a\u62df\u673a\u3002\r\n\r\nLinux kernel \u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u672c\u5730\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u53ef\u4ee5\u901a\u8fc7Linux\u5185\u6838\u7684BPF\u8bfb\u53d6\u5185\u5b58\u7247\u6bb5\uff0c\u4ee5\u83b7\u53d6\u654f\u611f\u4fe1\u606f\u3002 \u76ee\u524d\uff0c\u4f9b\u5e94\u5546\u53d1\u5e03\u4e86\u5b89\u5168\u516c\u544a\u53ca\u76f8\u5173\u8865\u4e01\u4fe1\u606f\uff0c\u4fee\u590d\u4e86\u6b64\u6f0f\u6d1e\u3002",
  "patchName": "Linux kernel\u4fe1\u606f\u6cc4\u9732\u6f0f\u6d1e\uff08CNVD-2021-34746\uff09\u7684\u8865\u4e01",
  "products": {
    "product": "Linux Linux kernel \u003c=5.12.1"
  },
  "referenceLink": "https://vigilance.fr/vulnerability/Linux-kernel-information-disclosure-via-BPF-35231",
  "serverity": "\u4f4e",
  "submitTime": "2021-05-07",
  "title": "Linux kernel\u4fe1\u606f\u6cc4\u9732\u6f0f\u6d1e\uff08CNVD-2021-34746\uff09"
}

CVE-2021-31829 (GCVE-0-2021-31829)

Vulnerability from cvelistv5 – Published: 2021-05-06 15:43 – Updated: 2024-08-03 23:10

Summary

kernel/bpf/verifier.c in the Linux kernel through 5.12.1 performs undesirable speculative loads, leading to disclosure of stack content via side-channel attacks, aka CID-801c6058d14a. The specific concern is not protecting the BPF stack area against speculative loads. Also, the BPF stack can contain uninitialized data that might represent sensitive information previously operated on by the kernel.

Severity

No CVSS data available.

CWE

Assigner

mitre mitre root

References

6 references

URL	Tags
http://www.openwall.com/lists/oss-security/2021/05/04/4	mailing-listx_refsource_MLIST
https://github.com/torvalds/linux/commit/801c6058…	x_refsource_MISC
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://lists.debian.org/debian-lts-announce/2021…	mailing-listx_refsource_MLIST

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.