Auth bypass in Linux Kernel
CVE-2021-31829
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.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (21.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 21.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Linux Kernel
- Debian Linux — versions 9.0
- Fedoraproject Fedora — versions 32, 33, 34
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.openwall.com/lists/oss-security/2021/05/04/4 (mailing-list, Patch, Mailing List, Third Party Advisory)
- github.com/torvalds/linux/commit/801c6058d14a82179a7ee17a4b532cac6fad067f (Patch, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.debian.org/debian-lts-announce/2021/06/msg00019.html (mailing-list, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-31829?
- CVE-2021-31829 is a medium-severity vulnerability in Linux Kernel, classified under Incorrect Authorization. CVSS score: 5.5/10. Published 2021-05-06.
- How severe is CVE-2021-31829?
- Medium severity. CVSS v3 base score is 5.5 out of 10.
- Is CVE-2021-31829 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.