CVE-2026-31431
In the Linux kernel, the following vulnerability has been resolved: crypto: algif_aead - Revert to operating out-of-place This mostly reverts commit 72548b093ee3 except for the copying of the associated data. There is no benefit in operating in-place in algif_aead since the source and destination come from different mappings. Get rid of all the complexity added for in-place operation and just copy the AD directly.
do firstUpgrade to a fixed release: < 4.14, >= 5.10.254 and <= 5.10.*, >= 5.15.204 and <= 5.15.*, >= 6.1.170 and <= 6.1.* (+5 more below).
Can a WAF block it? No. The attack needs local access to the machine, so a WAF is not on its path.
Also consider: patch
Based on the attack vector (local or physical access). We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Is CVE-2026-31431 being exploited?
Yes. CVE-2026-31431 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2026-31431?
CVE-2026-31431 is rated High with a CVSS score of 7.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-31431?
Yes. A fix has been recorded for CVE-2026-31431. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-31431 affect?
CVE-2026-31431 affects linux:linux_kernel, redhat:openshift_container_platform, redhat:enterprise_linux, redhat:enterprise_linux_aus, and 26 further products or versions. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < 893d22e0135fa394db81df88697fba6032747667
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < 19d43105a97be0810edbda875f2cd03f30dc130c
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < 961cfa271a918ad4ae452420e7c303149002875b
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < 3115af9644c342b356f3f07a4dd1c8905cd9a6fc
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < 8b88d99341f139e23bdeb1027a2a3ae10d341d82
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < fafe0fa2995a0f7073c1c358d7d3145bcc9aedd8
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < ce42ee423e58dffa5ec03524054c9d8bfd4f6237
- affected>= 72548b093ee38a6d4f2a19e6ef1948ae05c181f7 and < a664bf3d603dc3bdcf9ae47cc21e0daec706d7a5
- affected4.14
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
public exploits
Public exploit code: 1 Metasploit module · 326 GitHub proofs of concept
- exploit/linux/local/cve_2026_31431_copy_fail · exploit · excellent
- theori-io/copy-fail-CVE-2026-31431 · 4,084 ★
- tgies/copy-fail-c · 448 ★
- badsectorlabs/copyfail-go · 360 ★
- Percivalll/Copy-Fail-CVE-2026-31431-Kubernetes-PoC · 194 ★
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
cisa ssvc
- exploitation
- active
- automatable
- no
- technical impact
- total
Assessed by CISA 29 Apr 2026 (SSVC 2.0.3).
timeline
- 8 Mar 2026First public exploit or proof of concept
- 22 Apr 2026Published · 45 days later
- 29 Apr 2026CISA SSVC assessment: exploitation active · 7 days later
- 1 May 2026Added to CISA KEV (exploited in the wild) · 2 days later
- 15 May 2026CISA remediation due date (US federal agencies) · 14 days later
- 15 Oct 2026CVE record last updated · 153 days (about 5 months) later
- 2 Nov 2026Analysed by vulneraibility.com · 19 days later
- Exploitgithub.com /theori-io/copy-fail-CVE-2026-31431
- Mitigationxint.io /blog/copy-fail-linux-distributions#the-fix-6
- Mitigationlore.kernel.org /linux-cve-announce/2026042214-CVE-2026-31431-3d65@gregkh/
- Mitigationaccess.redhat.com /security/cve/cve-2026-31431#cve-details-mitigation
- Linkgit.kernel.org /stable/c/893d22e0135fa394db81df88697fba6032747667
- Linkgit.kernel.org /stable/c/19d43105a97be0810edbda875f2cd03f30dc130c
- Linkgit.kernel.org /stable/c/961cfa271a918ad4ae452420e7c303149002875b
- Linkgit.kernel.org /stable/c/3115af9644c342b356f3f07a4dd1c8905cd9a6fc
Show 42 more
- Linkgit.kernel.org /stable/c/8b88d99341f139e23bdeb1027a2a3ae10d341d82
- Linkgit.kernel.org /stable/c/fafe0fa2995a0f7073c1c358d7d3145bcc9aedd8
- Linkgit.kernel.org /stable/c/ce42ee423e58dffa5ec03524054c9d8bfd4f6237
- Linkgit.kernel.org /stable/c/a664bf3d603dc3bdcf9ae47cc21e0daec706d7a5
- Linkcisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-31431
- Linkopenwall.com /lists/oss-security/2026/04/29/23
- Linkcopy.fail
- Linkopenwall.com /lists/oss-security/2026/04/29/25
- Linkopenwall.com /lists/oss-security/2026/04/29/26
- Linkopenwall.com /lists/oss-security/2026/04/30/2
- Linkopenwall.com /lists/oss-security/2026/04/30/5
- Linkopenwall.com /lists/oss-security/2026/04/30/6
- Linkopenwall.com /lists/oss-security/2026/04/30/10
- Linkopenwall.com /lists/oss-security/2026/04/30/11
- Linkopenwall.com /lists/oss-security/2026/04/30/12
- Linkopenwall.com /lists/oss-security/2026/04/30/14
- Linkopenwall.com /lists/oss-security/2026/04/30/15
- Linkopenwall.com /lists/oss-security/2026/04/30/16
- Linkopenwall.com /lists/oss-security/2026/04/30/17
- Linkopenwall.com /lists/oss-security/2026/04/30/18
- Linkwebsec.net /blog/cve-2026-31431-linux-algifaead-page-cache-write-to-root-69f38a4ccddd2db1f5
- Linkopenwall.com /lists/oss-security/2026/04/30/20
- Linkopenwall.com /lists/oss-security/2026/05/01/2
- Linkopenwall.com /lists/oss-security/2026/05/01/3
- Linkopenwall.com /lists/oss-security/2026/05/01/10
- Linkopenwall.com /lists/oss-security/2026/05/01/12
- Linkopenwall.com /lists/oss-security/2026/05/01/15
- Linkopenwall.com /lists/oss-security/2026/05/01/16
- Linkopenwall.com /lists/oss-security/2026/05/01/17
- Linkopenwall.com /lists/oss-security/2026/05/01/18
- Linkopenwall.com /lists/oss-security/2026/05/01/22
- Linkopenwall.com /lists/oss-security/2026/05/01/23
- Linkopenwall.com /lists/oss-security/2026/05/01/24
- Linkopenwall.com /lists/oss-security/2026/05/02/4
- Linkopenwall.com /lists/oss-security/2026/05/02/5
- Linkopenwall.com /lists/oss-security/2026/05/02/6
- Linkopenwall.com /lists/oss-security/2026/05/02/7
- Linkopenwall.com /lists/oss-security/2026/05/02/8
- Linkopenwall.com /lists/oss-security/2026/05/02/14
- Linkopenwall.com /lists/oss-security/2026/05/02/15
- Linkopenwall.com /lists/oss-security/2026/05/02/16
- Linkopenwall.com /lists/oss-security/2026/05/02/17
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Metasploit Framework: exploit and scanner modules
- PoC-in-GitHub: GitHub repositories that claim a proof of concept
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.