CVE-2026-43333
What it is
In the Linux kernel, the following vulnerability has been resolved: bpf: reject direct access to nullable PTR_TO_BUF pointers check_mem_access() matches PTR_TO_BUF via base_type() which strips PTR_MAYBE_NULL, allowing direct dereference without a null check. Map iterator ctx->key and ctx->value are PTR_TO_BUF | PTR_MAYBE_NULL. On stop callbacks these are NULL, causing a kernel NULL dereference. Add a type_may_be_null() guard to the PTR_TO_BUF branch, matching the existing PTR_TO_BTF_ID pattern.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% 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: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-476 · NULL pointer dereference
- Record status
- Analyzed
Affected
- Linux Kernel < 5.15.203
- Linux Kernel < 6.1.168
- Linux Kernel < 6.6.134
- Linux Kernel < 6.12.81
- Linux Kernel < 6.18.22
- Linux Kernel < 6.19.12
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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-2026-43333.md and follow it. Check whether this project is affected by CVE-2026-43333. 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/10bc4a4dcded509c5d5c67d497900c3922c604cd
- https://git.kernel.org/stable/c/21a10c06ffae24cb01fd174a7ab7736001d2ea56
- https://git.kernel.org/stable/c/4f6c99dc0420f1a3d671c1b8ab8a7ac84d9cba09
- https://git.kernel.org/stable/c/63276547debc4d8a73eefb2c5273b2a905c961b0
- https://git.kernel.org/stable/c/70abd9d118da2f56beb4ec22e3a29becae373535
- https://git.kernel.org/stable/c/8755066f7bd0f4ac46a29d1708c7b20894539252
- https://git.kernel.org/stable/c/b0db1accbc7395657c2b79db59fa9fae0d6656f3
References
- https://git.kernel.org/stable/c/10bc4a4dcded509c5d5c67d497900c3922c604cd
- https://git.kernel.org/stable/c/21a10c06ffae24cb01fd174a7ab7736001d2ea56
- https://git.kernel.org/stable/c/4f6c99dc0420f1a3d671c1b8ab8a7ac84d9cba09
- https://git.kernel.org/stable/c/63276547debc4d8a73eefb2c5273b2a905c961b0
- https://git.kernel.org/stable/c/70abd9d118da2f56beb4ec22e3a29becae373535
- https://git.kernel.org/stable/c/8755066f7bd0f4ac46a29d1708c7b20894539252
- https://git.kernel.org/stable/c/b0db1accbc7395657c2b79db59fa9fae0d6656f3