CVE-2026-91926 json
Gss-ntlmssp: gss-ntlmssp: memory leak in ntlm_decode_target_info via duplicated av_pair entries in ntlm challenge
published last mo. modified 5d ago also EUVD-2026-78441
- cvss
- 3.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 31%
- public exploits
- 0
- none known
Summary
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.
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red hat product security vex CVE-2026-91926 updated cvss 3.7
gss-ntlmssp: gss-ntlmssp: memory leak in ntlm_decode_target_info via duplicated AV_PAIR entries in NTLM CHALLENGE
-
Red Hat Enterprise Linux 8 gssntlmsspaffected: workaround, no fix available “No mitigation is currently available that meets Red Hat Product Security's standards for usability, deployment, applicability, or stability.”
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.37% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
Affected products
- Red Hat Red Hat Enterprise Linux 8
Classification
- Weakness
-
- CWE-401 Missing Release of Memory after Effective Lifetime
References
-
access.redhat.com
/security/cve/CVE-2026-91926
vdb-entry
-
bugzilla.redhat.com
/show_bug.cgi?id=2533698
issue-tracking
Sources
- CVE List CVE-2026-91926
- NVD CVE-2026-91926
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