Vulnerability Description
PREVAIL is a Polynomial-Runtime EBPF Verifier using an Abstract Interpretation Layer. Prior to version 0.2.4, the abstract transformer in prevail treats writes through a T_CTX-typed base register as a silent no-op: do_mem_store in src/crab/ebpf_transformer.cpp only models T_STACK stores, and the checker's T_CTX bounds arm never tests AccessType::write. An attacker can craft an eBPF program that overwrites a context field (e.g., ctx->data), reload that field typed as T_PACKET, and dereference an attacker-controlled address — and prevail will report the program as safe. This issue has been patched in version 0.2.4.
Related Weaknesses (CWE)
References
- https://github.com/vbpf/prevail/commit/de65234f67d2608b54d12571edb585ead224363c
- https://github.com/vbpf/prevail/releases/tag/v0.2.4
- https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99
- https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99
FAQ
What is CVE-2026-53671?
CVE-2026-53671 is a documented vulnerability. PREVAIL is a Polynomial-Runtime EBPF Verifier using an Abstract Interpretation Layer. Prior to version 0.2.4, the abstract transformer in prevail treats writes through a T_CTX-typed base register as a...
How severe is CVE-2026-53671?
CVSS scoring is not yet available for CVE-2026-53671. Check NVD for updates.
Is there a patch for CVE-2026-53671?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.