{"id":"CVE-2026-89539","state":"PUBLISHED","title":"SUNRPC: reject duplicate CREDS_VALUE options","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.","publishedAt":"2026-09-11T19:44:16.699Z","updatedAt":"2026-10-30T12:32:05.658Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"6207d7df96b3a7f507f0bfc8842b3760ee2fb1f8","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"4904d61eb2e2bd484000725fd302b8f37b4fcf3a","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"64b9ef369a6f723294613cb129e5f62c35429df5","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"4b5ebb4f91a6152a0f7b1253f701197e5710d4da","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"f615b884310bf82d0014e3b5a92eb9aa88146685","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"7a1d0501cbb962beba23377035d667bf3c1726ee","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"9d94f046b23de0f77849ea69133063c949297e30","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"2e4ce62385c1b8a887c5370af058ac7b52a8eaf9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sunrpc/auth_gss/gss_rpc_xdr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.10","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.109","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","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/gss_rpc_xdr.c"]}],"references":["https://git.kernel.org/stable/c/6207d7df96b3a7f507f0bfc8842b3760ee2fb1f8","https://git.kernel.org/stable/c/4904d61eb2e2bd484000725fd302b8f37b4fcf3a","https://git.kernel.org/stable/c/64b9ef369a6f723294613cb129e5f62c35429df5","https://git.kernel.org/stable/c/4b5ebb4f91a6152a0f7b1253f701197e5710d4da","https://git.kernel.org/stable/c/f615b884310bf82d0014e3b5a92eb9aa88146685","https://git.kernel.org/stable/c/7a1d0501cbb962beba23377035d667bf3c1726ee","https://git.kernel.org/stable/c/9d94f046b23de0f77849ea69133063c949297e30","https://git.kernel.org/stable/c/2e4ce62385c1b8a887c5370af058ac7b52a8eaf9"],"weaknesses":[],"ingestedAt":"2026-10-30T12:50:04.827Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89539.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89539","state":"PUBLISHED","datePublished":"2026-09-11T19:44:16.699Z","dateUpdated":"2026-10-30T12:32:05.658Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.721Z"},"containers":{"cna":{"title":"SUNRPC: reject duplicate CREDS_VALUE options","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"6207d7df96b3a7f507f0bfc8842b3760ee2fb1f8","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"4904d61eb2e2bd484000725fd302b8f37b4fcf3a","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"64b9ef369a6f723294613cb129e5f62c35429df5","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"4b5ebb4f91a6152a0f7b1253f701197e5710d4da","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"f615b884310bf82d0014e3b5a92eb9aa88146685","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"7a1d0501cbb962beba23377035d667bf3c1726ee","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"9d94f046b23de0f77849ea69133063c949297e30","versionType":"git"},{"version":"1d658336b05f8697d6445834f8867f8ad5e4f735","status":"affected","lessThan":"2e4ce62385c1b8a887c5370af058ac7b52a8eaf9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sunrpc/auth_gss/gss_rpc_xdr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.10","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.109","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","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/gss_rpc_xdr.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/6207d7df96b3a7f507f0bfc8842b3760ee2fb1f8"},{"url":"https://git.kernel.org/stable/c/4904d61eb2e2bd484000725fd302b8f37b4fcf3a"},{"url":"https://git.kernel.org/stable/c/64b9ef369a6f723294613cb129e5f62c35429df5"},{"url":"https://git.kernel.org/stable/c/4b5ebb4f91a6152a0f7b1253f701197e5710d4da"},{"url":"https://git.kernel.org/stable/c/f615b884310bf82d0014e3b5a92eb9aa88146685"},{"url":"https://git.kernel.org/stable/c/7a1d0501cbb962beba23377035d667bf3c1726ee"},{"url":"https://git.kernel.org/stable/c/9d94f046b23de0f77849ea69133063c949297e30"},{"url":"https://git.kernel.org/stable/c/2e4ce62385c1b8a887c5370af058ac7b52a8eaf9"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:32:05.658Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"5.10.273"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"5.15.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.12.109"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.18.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}