{"id":"CVE-2025-71120","state":"PUBLISHED","title":"SUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf\n\nA zero length gss_token results in pages == 0 and in_token->pages[0]\nis NULL. The code unconditionally evaluates\npage_address(in_token->pages[0]) for the initial memcpy, which can\ndereference NULL even when the copy length is 0. Guard the first\nmemcpy so it only runs when length > 0.","publishedAt":"2026-01-14T15:06:07.194Z","updatedAt":"2026-10-19T18:15:14.623Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5866efa8cbfbadf3905072798e96652faf02dbe8","status":"affected","lessThan":"a8f1e445ce3545c90d69c9e8ff8f7821825fe810","versionType":"git"},{"version":"5866efa8cbfbadf3905072798e96652faf02dbe8","status":"affected","lessThan":"4dedb6a11243a5c9eb9dbb97bca3c98bd725e83d","versionType":"git"},{"version":"5866efa8cbfbadf3905072798e96652faf02dbe8","status":"affected","lessThan":"f9e53f69ac3bc4ef568b08d3542edac02e83fefd","versionType":"git"},{"version":"5866efa8cbfbadf3905072798e96652faf02dbe8","status":"affected","lessThan":"7452d53f293379e2c38cfa8ad0694aa46fc4788b","versionType":"git"},{"version":"5866efa8cbfbadf3905072798e96652faf02dbe8","status":"affected","lessThan":"a2c6f25ab98b423f99ccd94874d655b8bcb01a19","versionType":"git"},{"version":"5866efa8cbfbadf3905072798e96652faf02dbe8","status":"affected","lessThan":"1c8bb965e9b0559ff0f5690615a527c30f651dd8","versionType":"git"},{"version":"5866efa8cbfbadf3905072798e96652faf02dbe8","status":"affected","lessThan":"d4b69a6186b215d2dc1ebcab965ed88e8d41768d","versionType":"git"},{"version":"66ed7b413d31c6ff23901ac4443b1cc1af2f6113","status":"affected","versionType":"git"},{"version":"7be8c165dc81564705e8e0b72d398ef708f67eaa","status":"affected","versionType":"git"},{"version":"4.19.99","status":"affected","lessThan":"4.20","versionType":"semver"},{"version":"5.4.15","status":"affected","lessThan":"5.5","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sunrpc/auth_gss/svcauth_gss.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.248","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.198","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.160","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.120","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.64","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.3","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sunrpc/auth_gss/svcauth_gss.c"]}],"references":["https://git.kernel.org/stable/c/a8f1e445ce3545c90d69c9e8ff8f7821825fe810","https://git.kernel.org/stable/c/4dedb6a11243a5c9eb9dbb97bca3c98bd725e83d","https://git.kernel.org/stable/c/f9e53f69ac3bc4ef568b08d3542edac02e83fefd","https://git.kernel.org/stable/c/7452d53f293379e2c38cfa8ad0694aa46fc4788b","https://git.kernel.org/stable/c/a2c6f25ab98b423f99ccd94874d655b8bcb01a19","https://git.kernel.org/stable/c/1c8bb965e9b0559ff0f5690615a527c30f651dd8","https://git.kernel.org/stable/c/d4b69a6186b215d2dc1ebcab965ed88e8d41768d","https://cert-portal.siemens.com/productcert/html/ssa-019113.html","https://cert-portal.siemens.com/productcert/html/ssa-457936.html"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:10:04.440Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/71xxx/CVE-2025-71120.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-71120","state":"PUBLISHED","datePublished":"2026-01-14T15:06:07.194Z","dateUpdated":"2026-10-19T18:15:14.623Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:30:19.654Z"},"containers":{"cna":{"title":"SUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf\n\nA zero length gss_token results in pages == 0 and in_token->pages[0]\nis NULL. The code unconditionally evaluates\npage_address(in_token->pages[0]) for the initial memcpy, which can\ndereference NULL even when the copy length is 0. Guard the first\nmemcpy so it only runs when length > 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