CVE-2026-90463

Summary

A flaw was found in the sssd NSS responder. This input validation vulnerability allows a local attacker, by sending specially crafted service lookup requests to the NSS responder's UNIX socket, to cause an out-of-bounds read. This out-of-bounds read may lead to a denial of service (DoS) by crashing the NSS responder process. While unprivileged local clients can typically reach the socket, there is no evidence of privilege escalation or reliable data disclosure.

Affected Software

VendorProductVersion RangeStatus

Weaknesses

  • CWE-125: Out-of-bounds Read

Workarounds

To reduce exposure, restrict access to the SSSD NSS responder UNIX socket (/var/lib/sss/pipes/nss) to trusted local clients. This can be achieved by enforcing stricter socket permissions or explicit UID restrictions. While this reduces the attack surface, the underlying parser bug remains. Changes to socket permissions may require a restart of the SSSD service to take effect.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References