{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-89540", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-89540", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-09-11T19:44:17.440Z", "updatedAt": "2026-10-19T08:48:31.930Z", "importedAt": "2026-10-24T01:58:35.090Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "sunrpc: init gssp_lock before publishing proc entry", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nsunrpc: init gssp_lock before publishing proc entry\n\ncreate_use_gss_proxy_proc_entry() publishes /proc/net/rpc/use-gss-proxy\nvia proc_create_data() before init_gssp_clnt() runs mutex_init() on\nsn->gssp_lock. Once the dentry is linked under proc_subdir_lock it is\nimmediately reachable from userspace, so a write that lands in the\nwindow drives set_gssp_clnt() into mutex_lock() on a zero-initialized\nstruct mutex.\n\n create_use_gss_proxy_proc_entry(net)\n proc_create_data(\"use-gss-proxy\", ...) /* dentry live */\n init_gssp_clnt(sn)\n mutex_init(&sn->gssp_lock) /* too late */\n\n write_gssp()\n set_gssp_clnt(net)\n mutex_lock(&sn->gssp_lock) /* uninitialized */\n gssp_rpc_create(...)\n sn->gssp_clnt = clnt\n mutex_unlock(&sn->gssp_lock)\n\nThe window spans only the two statements between proc_create_data()\nreturning and init_gssp_clnt(), so a writer reaches it only if the\nregistering thread is preempted there while another task is already\nopening the freshly published file. register_pernet_subsys() runs in\npreemptible context under pernet_ops_rwsem, so that preemption is\npossible, and the window widens on auth_rpcgss module load, when the\nproc entry is created for every live net namespace whose tasks are\nalready running. A writer that wins the race locks a zero-filled\nstruct mutex. On CONFIG_DEBUG_MUTEXES the missing magic value trips a\n\"lock used without init\" splat; on a production kernel the fast path\nacquires the lock via CMPXCHG(owner, 0, current). In the latter case\na second writer that arrives before init_gssp_clnt() re-zeroes owner\ncan enter set_gssp_clnt() concurrently, shut down the first writer's\nclnt while it is still in use, and leak the loser's clnt.\n\nFix by initializing sn->gssp_lock in sunrpc_init_net() so its lifetime\nmatches the sunrpc_net it lives in. sn->gssp_clnt is already NULL from\nthe kzalloc that backs net_generic storage, so the lazy helper is no\nlonger needed; drop init_gssp_clnt(), its prototype, and the call from\ncreate_use_gss_proxy_proc_entry(). sunrpc.ko is a build-time\ndependency of auth_rpcgss.ko, so sunrpc_init_net() has always run on\nevery netns before any auth_gss pernet init can publish the proc\nentry.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "159a4fab7170badd6c4a553aef81cac079d6f4ee" }, { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "b3526ae3351968f6726bcbe25d8d09973ad79109" }, { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "7f5bcdc8da15077ebe846c2756a5a17741021410" }, { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "89c8e0733e8c46b7973503f15b1b31a8587d8030" }, { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "f15b87521168c2a92cb1931f532cba422f856f01" }, { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "edeefb111d6181a4aa278f415b005efe284b9489" }, { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "3f019571928b269feebcff59926ec13294215e0e" }, { "version": "030d794bf49855f5e2a9e8dfbfad34211d1eb08b", "status": "affected", "versionType": "git", "lessThan": "5ce1ed6159731a41fdd0b03eedbed4e147036a5a" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "3.10", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "3.10" }, { "version": "5.10.270", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.221", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.188", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.157", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.109", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.50", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.2.4", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.2.*" }, { "version": "7.3", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }