Vulnerability in Linux Kernel
CVE-2021-33624
In kernel/bpf/verifier.c in the Linux kernel before 5.12.13, a branch can be mispredicted (e.g., because of type confusion) and consequently an unprivileged BPF program can read arbitrary memory locations via a side-channel attack, aka CID-9183671af6db.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.009 (59.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 59.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000
Affected products
- Linux Kernel
- Debian Linux — versions 9.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.usenix.org/conference/usenixsecurity21/presentation/kirzner (Third Party Advisory)
- www.openwall.com/lists/oss-security/2021/06/21/1 (Exploit, Mailing List, Third Party Advisory)
- github.com/torvalds/linux/commit/9183671af6dbf60a1219371d4ed73e23f43b49db (Patch, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2021/10/msg00010.html (mailing-list, Third Party Advisory, Issue Tracking)
- github.com/benschlueter/CVE-2021-33624
Frequently asked questions
- What is CVE-2021-33624?
- CVE-2021-33624 is a medium-severity vulnerability in Linux Kernel, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 4.7/10. Published 2021-06-23.
- How severe is CVE-2021-33624?
- Medium severity. CVSS v3 base score is 4.7 out of 10.
- Is CVE-2021-33624 known to be exploited?
- 11 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.