What’s Vulnerable › Vulnerabilities

CVE-2020-25212

• Severity: high (CVSS 7.0 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-09-09 · updated 2026-06-17
• Weakness: CWE-367

Description

A TOCTOU mismatch in the NFS client code in the Linux kernel before 5.8.3 could be used by local attackers to corrupt memory or possibly have unspecified other impact because a size check is in fs/nfs/nfs4proc.c instead of fs/nfs/nfs4xdr.c, aka CID-b4487b935452.

Affected products

• Canonical Ubuntu Linux: 14.04, 16.04, 18.04, 20.04
• Debian Linux: 9.0
• Linux kernel: before 5.8.3 — fixed in 5.8.3
• openSUSE Leap: 15.1, 15.2

How to fix

Upgrade to a fixed version: Linux kernel 5.8.3. Check the vendor advisory for mitigations.

References

• http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00021.html
• http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00035.html
• http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00042.html
• https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.8.3
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b4487b93545214a9db8cbf32e86411677b0cca21
• https://lists.debian.org/debian-lts-announce/2020/09/msg00025.html
• https://lists.debian.org/debian-lts-announce/2020/10/msg00032.html
• https://lists.debian.org/debian-lts-announce/2020/10/msg00034.html
• https://twitter.com/grsecurity/status/1303370421958578179
• https://usn.ubuntu.com/4525-1/
• https://usn.ubuntu.com/4527-1/
• https://usn.ubuntu.com/4578-1/

Get alerted when CVE-2020-25212 or the next vulnerability affects your stack