What’s Vulnerable › Vulnerabilities

CVE-2025-71120: SUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-01-14 · updated 2026-10-19
• Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf A zero length gss_token results in pages == 0 and in_token->pages[0] is NULL. The code unconditionally evaluates page_address(in_token->pages[0]) for the initial memcpy, which can dereference NULL even when the copy length is 0. Guard the first memcpy so it only runs when length > 0.

Affected products

• Linux kernel: from 4.19.99 before 4.20; from 5.4.15 before 5.5; from 5.5.1 before 5.10.248; from 5.11 before 5.15.198; from 5.16 before 6.1.160; from 6.2 before 6.6.120 — fixed in 4.20, 5.10.248, 5.15.198, 5.5, 6.1.160, 6.12.64

How to fix

Upgrade to a fixed version: Linux kernel 4.20, 5.10.248, 5.15.198, 5.5. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/1c8bb965e9b0559ff0f5690615a527c30f651dd8
• https://git.kernel.org/stable/c/4dedb6a11243a5c9eb9dbb97bca3c98bd725e83d
• https://git.kernel.org/stable/c/7452d53f293379e2c38cfa8ad0694aa46fc4788b
• https://git.kernel.org/stable/c/a2c6f25ab98b423f99ccd94874d655b8bcb01a19
• https://git.kernel.org/stable/c/a8f1e445ce3545c90d69c9e8ff8f7821825fe810
• https://git.kernel.org/stable/c/d4b69a6186b215d2dc1ebcab965ed88e8d41768d
• https://git.kernel.org/stable/c/f9e53f69ac3bc4ef568b08d3542edac02e83fefd
• https://cert-portal.siemens.com/productcert/html/ssa-019113.html
• https://cert-portal.siemens.com/productcert/html/ssa-457936.html

Get alerted when CVE-2025-71120 or the next vulnerability affects your stack