CVE-2026-91926

A flaw was found in gss-ntlmssp. A memory leak occurs in the NTLM target-info parser when a crafted NTLM CHALLENGE message contains duplicated string-valued AV_PAIR entries. The parser allocates memory for each string value but does not free the previous allocation when the same AV_PAIR type appears more than once, leaking the earlier allocation. A malicious or man-in-the-middle server can exploit this to cause gradual memory exhaustion on the client during NTLM authentication, leading to a denial of service.

  • Published Sep 15, 2026
  • CVSS 3.7 low
  • 0.4% chance of exploitation in the next 30 days (EPSS)

Affected software

CVE-2026-91926 at the National Vulnerability Database