CVE Catalog

CVE-2026-93138

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.18%

7th percentile - higher than 7% of all known CVEs

Summary

In the Linux kernel, bpf_get_btf_vmlinux() has a race condition when publishing the parsed vmlinux BTF result. The result is published via a plain store and read locklessly, which on weakly ordered architectures could allow observing the pointer before initialized data is visible. The fix adds memory barriers (smp_store_release/smp_load_acquire).

Risk Assessment

Potential reading of incomplete BTF data by BPF programs, possibly leading to incorrect behavior or system crash.

Recommendation

Apply the kernel update to ensure proper memory ordering in bpf_get_btf_vmlinux().

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux bpf_get_btf_vmlinux() lazily parses the vmlinux BTF under the bpf_verifier_lock, but publishes the result through a plain store and re-checks it through a plain lockless load. Nothing orders the stores initializing the struct btf inside btf_parse_vmlinux() against the store publishing the pointer: On a weakly ordered arch, a concurrent first-time caller taking the lockless fast path could in principle observe the pointer before the parsed contents are visible. The mutex_unlock() does not help such a reader given it only synchronizes with a later acquisition of the same lock. Thus, publish the pointer with smp_store_release() and read it on the fast path with smp_load_acquire(). Acquire semantics are needed rather than a dependency-ordered READ_ONCE(): btf_parse_vmlinux() also populates globals outside the returned object (e.g. bpf_ctx_convert.t). An address dependency would only order accesses performed through the pointer and not cover other globals.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS