How severe is CVE-2026-31431?

CVE-2026-31431 has a CVSS score of 7.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-31431?

CVE-2026-31431 affects the following packages: Kernel (Linux). Ecosystems affected: Linux.

How do I fix CVE-2026-31431?

Update Kernel to 5.10.254 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-31431 is resolved across your whole dependency graph.

How do I detect CVE-2026-31431 in my Linux dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Kernel, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-31431 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2026-31431 actively exploited in the wild?

Yes. There are 77 known exploit references for CVE-2026-31431, including . All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2026-31431?

CVE-2026-31431 has an EPSS (Exploit Prediction Scoring System) score of 3.4%, placing it in the 89th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

Is CVE-2026-31431 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2026-31431 (Linux Kernel Incorrect Resource Transfer Between Spheres Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2026-05-01. CISA required all US federal civilian agencies to remediate this vulnerability by 2026-05-15. The required action was: "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2026-31431?

CVE-2026-31431 is classified as CWE-669 (CWE-669), CWE-1288 (CWE-1288). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-31431 published, and has it been updated?

CVE-2026-31431 was published on April 22, 2026 and was last updated on October 20, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐧

🐧 Linux

CISA KEV · ACTIVELY EXPLOITED

HIGH severity

CVE-2026-31431 — Kernel

HIGH

CVE-2026-31431 is a high-severity (CVSS 7.8) CWE-669 vulnerability in Kernel. It is in CISA's Known Exploited Vulnerabilities catalog (added 2026-05-01) — treat it as actively exploited and patch now. A fix is available for Kernel — see the affected versions and patch details below.

crypto: algif_aead - Revert to operating out-of-place

Published

Apr 22, 2026

Updated

Oct 20, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

77 known

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2026-05-01. Federal agencies were required to remediate by 2026-05-15.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2026-31431.

EPSS Exploitation Probability

via FIRST.org ↗

3.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs89th percentile — riskier than 89% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2026-31431 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🐧Kernel

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Linux packages — download data is not available via public APIs for these ecosystems.

Description

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐧Linux	`Kernel`	≥ 4.14.0&&< 5.10.254	5.10.254

Affected Products

48 products · 207 configurations

amazon linuxamazon

all

Application

cloudvision agniarista

≥ 2024.4.0 && ≤ 2025.2.2

range

Application

cloudvision portalarista

≥ 2024.2.0 && ≤ 2026.1.0

range

netvisor osarista

< 7.1.0

1 version

7.1.0

Application

velocloud edgearista

≥ 4.5.0 && ≤ 6.4.1

range

Application

velocloud gatewayarista

all

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

theori-io/copy-fail-CVE-2026-31431

Copy Fail (CVE-2026-31431): 9-year-old Linux kernel LPE found by Theori'

⭐ 4,075🍴 912Sep 2026

tgies/copy-fail-c

Cross-platform C port of the Copy Fail Linux LPE (CVE-2026-31431). Discl

⭐ 443🍴 119Sep 2026

badsectorlabs/copyfail-go

A Go implementation of copyfail (CVE-2026-31431)

⭐ 359🍴 76Sep 2026

Percivalll/Copy-Fail-CVE-2026-31431-Kubernetes-PoC

PoC: fully unprivileged container escape to node-level code execution on

⭐ 190🍴 26Sep 2026

Sndav/CVE-2026-31431-Advanced-Exploit

CVE-2026-31431 纯文件利用

⭐ 111🍴 29Aug 2026

painoob/Copy-Fail-Exploit-CVE-2026-31431

Most Linux LPEs need a race window or a kernel-specific offset. Copy Fai

⭐ 109🍴 23Sep 2026

sgkdev/page_inject

CVE-2026-31431-killed page-cache exploit — code exec into containers sha

⭐ 76🍴 13Sep 2026

Crihexe/copy-fail-tiny-elf-CVE-2026-31431

Minimal no-libc Linux x86_64 ELF PoC build for Copy Fail (CVE-2026-31431

⭐ 63🍴 10Aug 2026

shadowabi/CVE-2026-31431-CopyFail-Universal-LPE

CVE-2026-31431 Copy Fail — Universal LPE exploit. Dynamic ELF offset + f

⭐ 58🍴 12Sep 2026

iss4cf0ng/CVE-2026-31431-Linux-Copy-Fail

Rust implementation Exploit/PoC of CVE-2026-31431-Linux-Copy-Fail, allow

⭐ 55🍴 21Sep 2026

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Kernel, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Kernel to 5.10.254 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-31431 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatImportant

This issue is classified as Important, rather than Critical severity, because exploitation requires local access to the system. A low-privileged local attacker can exploit this flaw in the Linux kernel's cryptographic interface to gain root privileges by overwriting sensitive system files. Exploitation does not…

Workaround published by Red Hat

See the security bulletin for a detailed mitigation procedure.

Source: Red Hat security advisory for CVE-2026-31431 (CC BY 4.0)

Product	Fixed in	Advisory
NVIDIA for RHEL 10	`kernel-0:6.12.0-211.6.el10nv`	RHSA-2026:14926
NVIDIA for RHEL 10	`kernel-0:6.12.0-231.12.el10nv`	RHSA-2026:33486
Red Hat Enterprise Linux 10	`kernel-0:6.12.0-124.55.1.el10_1`	RHSA-2026:13566
Red Hat Enterprise Linux 10	`kernel-0:6.12.0-211.7.3.el10_2`	RHSA-2026:19074
Red Hat Enterprise Linux 10.0 Extended Update Support	`kernel-0:6.12.0-55.71.1.el10_0`	RHSA-2026:13887
Red Hat Enterprise Linux 8	`kernel-rt-0:4.18.0-553.123.1.rt7.464.el8_10`	RHSA-2026:13578
Red Hat Enterprise Linux 8	`kernel-0:4.18.0-553.123.1.el8_10`	RHSA-2026:13577
Red Hat Enterprise Linux 8	`kpatch-patch`	RHSA-2026:15976

UbuntuHIGH

USN-8226-1Ubuntu USN-8226-2Ubuntu USN-8277-1Ubuntu USN-8278-1Ubuntu USN-8279-1Ubuntu USN-8280-1Ubuntu USN-8281-1Ubuntu USN-8289-1Ubuntu

Frequently Asked Questions

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.

O3 Security · Impact-Aware SCA

Is CVE-2026-31431 in your dependencies?

Find it across Linux, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVE-2026-31431 — Kernel

Exploitation Status

Actively exploited in the wild

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2026-31431 in your dependencies?