CVE-2021-31829
Status: ModifiedMedium (5.5)—
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.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- Base score: 5.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.31%
- Percentile among all scored CVEs: 22
- Score date: 10/12/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (3)
CWEs
- CWE-863
References
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- https://github.com/torvalds/linux/commit/801c6058d14a82179a7ee17a4b532cac6fad067f
- https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VWCZ6LJLENL2C3URW5ICARTACXPFCFN2/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y4X2G5YAPYJGI3PFEZZNOTRYI33GOCCZ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZI7OBCJQDNWMKLBP6MZ5NV4EUTDAMX6Q/
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- http://www.openwall.com/lists/oss-security/2021/05/04/4
- https://github.com/torvalds/linux/commit/801c6058d14a82179a7ee17a4b532cac6fad067f
- https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VWCZ6LJLENL2C3URW5ICARTACXPFCFN2/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y4X2G5YAPYJGI3PFEZZNOTRYI33GOCCZ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZI7OBCJQDNWMKLBP6MZ5NV4EUTDAMX6Q/
Raw JSON (NVD)
Show
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