CVE-2026-45903
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIn the Linux kernel, the following vulnerability has been resolved: bpf: Fix memory access flags in helper prototypes After commit 37cce22dbd51 ("bpf: verifier: Refactor helper access type tracking"), the verifier started relying on the access type flags in helper function prototypes to perform memory access optimizations. Currently, several helper functions utilizing ARG_PTR_TO_MEM lack the corresponding MEM_RDONLY or MEM_WRITE flags. This omission causes the verifier to incorrectly assume that the buffer contents are unchanged across the helper call. Consequently, the verifier may optimize away subsequent reads based on this wrong assumption, leading to correctness issues. For bpf_get_stack_proto_raw_tp, the original MEM_RDONLY was incorrect since the helper writes to the buffer. Change it to ARG_PTR_TO_UNINIT_MEM which correctly indicates write access to potentially uninitialized memory. Similar issues were recently addressed for specific helpers in commit ac44dcc788b9 ("bpf: Fix verifier assumptions of bpf_d_path's output buffer") and commit 2eb7648558a7 ("bpf: Specify access type of bpf_sysctl_get_name args"). Fix these prototypes by adding the correct memory access flags.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysisThe code reads past the end (or before the start) of a buffer, returning memory that was never meant to be exposed. Attackers use it to leak secrets like keys or to defeat memory-protection defences. Remediation is validating indices and lengths before every read.
General guidance for the out-of-bounds read class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 6.14, < 6.18.14>= 6.19, < 6.19.4CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped6.18.146.19.4
Linux Kernel 6.18.14 or 6.19.4 (or later stable releases)
- Check current kernel version using 'uname -r' or 'cat /proc/version'
- If running kernel >= 6.14 and < 6.18.14, upgrade to kernel version 6.18.14 or later
- If running kernel >= 6.19 and < 6.19.4, upgrade to kernel version 6.19.4 or later
- Alternatively, apply the vendor patch from commit 802eef5afb1865bc5536a5302c068ba2215a1f72 to rebuild the kernel with the fix
- Reboot into the updated kernel and verify the fix is applied
Generated from the published advisory — verify against the referenced sources before acting.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-45903 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-45903 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data