Firewall bypass via stale AVX2 match bits
Published May 6, 2026 · Updated Aug 26, 2026
Incorrect nftables matching in affected Linux kernels allows remote attackers to bypass firewall policy via crafted packet keys. The AVX2 PIPAPO match functions return before consuming the final field, leaving stale map bits that can select an entry matching only the first field. Reachability requires an AVX2 concatenated or interval set with expired or inactive entries; false matches can admit unauthorized traffic or reject valid set updates.
Summary
What happened
Incorrect nftables matching in affected Linux kernels allows remote attackers to bypass firewall policy via crafted packet keys. The AVX2 PIPAPO match functions return before consuming the final field, leaving stale map bits that can select an entry matching only the first field. Reachability requires an AVX2 concatenated or interval set with expired or inactive entries; false matches can admit unauthorized traffic or reject valid set updates.
The record
- CVE
- CVE-2026-43114
- Published
- May 6, 2026
- Updated
- Aug 26, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 6, 2026CVE publishedPublication date reported by the CVE source.
- Aug 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.7
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <07de44424bb7f17ef9357e8535df96d9e97c40cb
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <0abbc43f71d99baadeeba6fa3fe1c80b676f57ed
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <1c43f0dd8691ddf8884793b481ddc7511cf593c3
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <3d53f9aafd469ae1ea27051e00f5b96ca1b55d52
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <c7babe2f28b507e17f28e9f753b7caec72d4857f
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <d3c0037ffe1273fa1961e779ff6906234d6cf53c
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <f8c39983fc9c1a978c82e6f2df7bfba8a8561587
- Affected versionversion=7400b063969bdca4a06cd97f1294d765c8eecbe1 <fa4f1f52528c73989d820f32bfca06bec5afeece
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo