{"cve":"CVE-2026-89539","nvd":{"published":"2026-09-11T20:19:36.977","modified":"2026-10-21T13:20:07.850","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: reject duplicate CREDS_VALUE options\n\ngssx_dec_option_array() walks the wire-supplied option array and, for\nevery entry whose name matches CREDS_VALUE, calls\ngssx_dec_linux_creds() on the same struct svc_cred. That helper\nunconditionally installs a fresh groups_alloc() result into\ncreds->cr_group_info without releasing whatever pointer was already\nthere:\n\n    for (i = 0; i < count; i++) {\n        ... decode name ...\n        if (length == sizeof(CREDS_VALUE) &&\n            memcmp(p, CREDS_VALUE, sizeof(CREDS_VALUE)) == 0) {\n            err = gssx_dec_linux_creds(xdr, creds);\n            ...\n        }\n    }\n\nA reply that carries two CREDS_VALUE entries therefore overwrites\ncr_group_info on the second iteration and orphans the group_info\nallocated by the first call. The earlier free_creds path only\nreleases the last cr_group_info via free_svc_cred(), so the first\nallocation's refcount stays at one and its kvmalloc-backed storage\nis leaked. No in-tree caller of gssp_accept_sec_context_upcall()\nexpects more than one CREDS_VALUE per reply.\n\nFix by tracking whether a CREDS_VALUE option has already been\ndecoded and returning -EINVAL on any subsequent match, so the\nfree_creds path releases the single group_info that was installed.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/2e4ce62385c1b8a887c5370af058ac7b52a8eaf9","https://git.kernel.org/stable/c/4b5ebb4f91a6152a0f7b1253f701197e5710d4da","https://git.kernel.org/stable/c/7a1d0501cbb962beba23377035d667bf3c1726ee","https://git.kernel.org/stable/c/9d94f046b23de0f77849ea69133063c949297e30","https://git.kernel.org/stable/c/f615b884310bf82d0014e3b5a92eb9aa88146685"],"products":[],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-89539","score":0.00168,"percentile":0.06149,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}