Vulnerability · Published Sep 2, 2026 · Assigned by GitHub_M
CVE-2026-53706PREVAIL: ALU32 pointer arithmetic accepted without is64 gate — verifier emits false PASS for pointer-corrupting programs
High 8.8
In plain English
A high-severity security flaw in prevail from vbpf. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities).
Official description
PREVAIL is a Polynomial-Runtime EBPF Verifier using an Abstract Interpretation Layer. Prior to version 0.2.4, the prevail eBPF verifier accepts ALU32 ADD and SUB instructions that operate on pointer-typed registers without checking the is64 flag. Because ALU32 arithmetic zero-extends the 32-bit result, the upper half of any pointer is silently destroyed at runtime, yet prevail marks the program as verified safe. Any caller that can submit an eBPF program for verification — including unprivileged users on kernels that permit BPF program loading — can produce a program that passes verification but faults or misbehaves at runtime. This issue has been patched in version 0.2.4.
Affected products (as reported)
Weakness: CWE-682 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N
References
- https://github.com/vbpf/prevail/security/advisories/GHSA-65fp-5qmq-gg2m x_refsource_CONFIRM
- https://github.com/vbpf/prevail/commit/d3fab8c23a93d9a615bc741b254ab26391559e0f x_refsource_MISC
- https://github.com/vbpf/prevail/releases/tag/v0.2.4 x_refsource_MISC