CVE-2026-91926 (GCVE-0-2026-91926)
Vulnerability from cvelistv5 – Published: 2026-09-15 11:49 – Updated: 2026-09-15 11:49
VLAI
EPSS
VEX
Title
Gss-ntlmssp: gss-ntlmssp: memory leak in ntlm_decode_target_info via duplicated av_pair entries in ntlm challenge
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.
Severity
CWE
- CWE-401 - Missing Release of Memory after Effective Lifetime
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-91926 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2533698 | issue-trackingx_refsource_REDHAT |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8
|
Date Public
2026-09-15 00:00
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"title": "gss-ntlmssp: gss-ntlmssp: memory leak in ntlm_decode_target_info via duplicated AV_PAIR entries in NTLM CHALLENGE",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91926.json",
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}
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
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- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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