CVE-2025-39931
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Set merge to zero early in af_alg_sendmsg If an error causes af_alg_sendmsg to abort, ctx->merge may contain a garbage value from the previous loop. This may then trigger a crash on the next entry into af_alg_sendmsg when it attempts to do a merge that can't be done. Fix this by setting ctx->merge to zero near the start of the loop.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-10-04 08:15:45.827000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
{
"id": "CVE-2025-39931",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-10-04T08:15:45.827",
"lastModified": "2026-10-19T21:10:00.160",
"vulnStatus": "Modified",
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{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: af_alg - Set merge to zero early in af_alg_sendmsg\n\nIf an error causes af_alg_sendmsg to abort, ctx->merge may contain\na garbage value from the previous loop. This may then trigger a\ncrash on the next entry into af_alg_sendmsg when it attempts to do\na merge that can't be done.\n\nFix this by setting ctx->merge to zero near the start of the loop."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ncrypto: af_alg - Establecer merge a cero al principio en af_alg_sendmsg\n\nSi un error causa que af_alg_sendmsg aborte, ctx->merge puede contener un valor basura del bucle anterior. Esto puede entonces desencadenar un bloqueo en la siguiente entrada en af_alg_sendmsg cuando intente hacer un merge que no se puede hacer.\n\nCorregir esto estableciendo ctx->merge a cero cerca del inicio del bucle."
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