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TI-2023-10867 Aliases CVE-2023-25564

GSS-NTLMSSP vulnerable to memory corruption when decoding UTF16 strings

Priority LOW 39CWE-787Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

GSS-NTLMSSP is a mechglue plugin for the GSSAPI library that implements NTLM authentication. Prior to version 1.2.0, memory corruption can be triggered when decoding UTF16 strings. The variable `outlen` was not initialized and could cause writing a zero to an arbitrary place in memory if `ntlm_str_convert()` were to fail, which would leave `outlen` uninitialized. This can lead to a denial of service if the write hits unmapped memory or randomly corrupts a byte in the application memory space. This vulnerability can trigger an out-of-bounds write, leading to memory corruption. This vulnerability can be triggered via the main `gss_accept_sec_context` entry point. This issue is fixed in version 1.2.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01942 80th percentileScored 2026-11-07
Fix Fixed gss-ntlmssp (gssapi): 1.2.0Red Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
gssapigss-ntlmsspbefore 1.2.01.2.0Patch availableCNA
  • gss-ntlmssp Vendorgssapi Affected before 1.2.0 Fixed in 1.2.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:gss-ntlmssp_project:gss-ntlmssp:*:*:*:*:*:*:*:*before 1.2.0Vulnerablegssapi
  • cpe:2.3:a:gss-ntlmssp_project:gss-ntlmssp:*:*:*:*:*:*:*:* Versions before 1.2.0 Vulnerable ·gssapi

Remediation

  • Fix · CNA gss-ntlmssp (gssapi) Fixed in 1.2.0

Red Hat 1 advisory

  • RHSA-2023:3097 Released 2023-05-16 · Red Hat rating Moderate
    gssntlmssp security update
    • Red Hat Enterprise Linux AppStream (v. 8) gssntlmssp-1.2.0-1.el8_8

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2023:3097

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-25564

References

Patch 1

Advisory 2

  • TI-2023-10870 GSS-NTLMSSP vulnerable to out-of-bounds read when decoding target information CVSS 3.1HIGH 7.5
  • TI-2023-10869 GSS-NTLMSSP vulnerable to memory leak when parsing usernames CVSS 3.1HIGH 7.5
  • TI-2023-10868 GSS-NTLMSSP vulnerable to incorrect free when decoding target information CVSS 3.1HIGH 7.5
  • TI-2023-10866 GSS-NTLMSSP vulnerable to multiple out-of-bounds reads when decoding NTLM fields CVSS 3.1HIGH 7.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences