CVE-2026-31431
Linux Kernel Incorrect Resource Transfer Between Spheres Vulnerability
Linux Kernel
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.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 1 May 2026. US federal agencies were required to remediate it by 15 May 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 98.1%, which is higher than 99.9% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2026-31431 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2026-31431.
What does CVE-2026-31431 affect?
CVE-2026-31431 affects Linux Kernel. 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.
How severe is CVE-2026-31431?
CVE-2026-31431 is rated HIGH with a CVSS base score of 7.8. EPSS puts the probability of exploitation in the next 30 days at 98.1%, higher than 99.9% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 15 May 2026.
How should organisations respond to CVE-2026-31431?
Apply the vendor patch for Linux Kernel as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.