CVE-2021-47317
What it is
In the Linux kernel, the following vulnerability has been resolved: powerpc/bpf: Fix detecting BPF atomic instructions Commit 91c960b0056672 ("bpf: Rename BPF_XADD and prepare to encode other atomics in .imm") converted BPF_XADD to BPF_ATOMIC and added a way to distinguish instructions based on the immediate field. Existing JIT implementations were updated to check for the immediate field and to reject programs utilizing anything more than BPF_ADD (such as BPF_FETCH) in the immediate field. However, the check added to powerpc64 JIT did not look at the correct BPF instruction. Due to this, such programs would be accepted and incorrectly JIT'ed resulting in soft lockups, as seen with the atomic bounds test. Fix this by looking at the correct immediate value.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-667
- Record status
- Modified
Affected
- Linux Kernel < 5.12.19
- Linux Kernel < 5.13.4
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-47317.md and follow it. Check whether this project is affected by CVE-2021-47317. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2
- https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94c
- https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2f
- https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2
- https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94c
- https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2f
References
- https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2
- https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94c
- https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2f
- https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2
- https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94c
- https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2f