CVE-2026-89539
In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: reject duplicate CREDS_VALUE options
gssx_dec_option_array() walks the wire-supplied option array and, for every entry whose name matches CREDS_VALUE, calls gssx_dec_linux_creds() on the same struct svc_cred. That helper unconditionally installs a fresh groups_alloc() result into creds->cr_group_info without releasing whatever pointer was already there:
A reply that carries two CREDS_VALUE entries therefore overwrites cr_group_info on the second iteration and orphans the group_info allocated by the first call.
Leer descripción completaMostrar menos
The earlier free_creds path only releases the last cr_group_info via free_svc_cred(), so the first allocation's refcount stays at one and its kvmalloc-backed storage is leaked. No in-tree caller of gssp_accept_sec_context_upcall() expects more than one CREDS_VALUE per reply.
Fix by tracking whether a CREDS_VALUE option has already been decoded and returning -EINVAL on any subsequent match, so the free_creds path releases the single group_info that was installed.
Detalles técnicos trazas, registros y código del informe original
for (i = 0; i < count; i++) {
... decode name ...
if (length == sizeof(CREDS_VALUE) &&
memcmp(p, CREDS_VALUE, sizeof(CREDS_VALUE)) == 0) {
err = gssx_dec_linux_creds(xdr, creds);
...
}
}CVSS
NVD no ha asignado puntuación CVSS a esta CVE (habitual desde el cambio de política de abril de 2026).
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.17%
- Percentil entre todas las CVEs puntuadas: 6
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-89539",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "1d658336b05f8697d6445834f8867f8ad5e4f735",
"lessThan": "f615b884310bf82d0014e3b5a92eb9aa88146685",
"versionType": "git"
},
{
"status": "affected",
"version": "1d658336b05f8697d6445834f8867f8ad5e4f735",
"lessThan": "7a1d0501cbb962beba23377035d667bf3c1726ee",
"versionType": "git"
},
{
"status": "affected",
"version": "1d658336b05f8697d6445834f8867f8ad5e4f735",
"lessThan": "9d94f046b23de0f77849ea69133063c949297e30",
"versionType": "git"
},
{
"status": "affected",
"version": "1d658336b05f8697d6445834f8867f8ad5e4f735",
"lessThan": "2e4ce62385c1b8a887c5370af058ac7b52a8eaf9",
"versionType": "git"
}
],
"programFiles": [
"net/sunrpc/auth_gss/gss_rpc_xdr.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.10"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.10",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3-rc1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sunrpc/auth_gss/gss_rpc_xdr.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-11T20:19:36.977",
"references": [
{
"url": "https://git.kernel.org/stable/c/2e4ce62385c1b8a887c5370af058ac7b52a8eaf9",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7a1d0501cbb962beba23377035d667bf3c1726ee",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/9d94f046b23de0f77849ea69133063c949297e30",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f615b884310bf82d0014e3b5a92eb9aa88146685",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"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."
}
],
"lastModified": "2026-09-11T20:19:36.977",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}