CVE-2023-25563: GSS-NTLMSSP vulnerable to multiple out-of-bounds reads when decoding NTLM fields

Published Feb 14, 2023
·
Updated

GSS-NTLMSSP is a mechglue plugin for the GSSAPI library that implements NTLM authentication. Prior to version 1.2.0, multiple out-of-bounds reads when decoding NTLM fields can trigger a denial of service. A 32-bit integer overflow condition can lead to incorrect checks of consistency of length of internal buffers. Although most applications will error out before accepting a singe input buffer of 4GB in length this could theoretically happen. This vulnerability can be triggered via the main gssacceptseccontext entry point if the application allows tokens greater than 4GB in length. This can lead to a large, up to 65KB, out-of-bounds read which could cause a denial-of-service if it reads from unmapped memory. Version 1.2.0 contains a patch for the out-of-bounds reads.

Affected Software

1 affected component
Gss-ntlmssp Project Gss-ntlmssp<1.2.0

Event History

Feb 14, 2023
CVE Published
via MITRE·05:35 PM
Data Sourced
via MITRE·05:35 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is CVE-2023-25563?

CVE-2023-25563 is a vulnerability in the GSS-NTLMSSP mechglue plugin for the GSSAPI library, which can lead to a denial of service due to multiple out-of-bounds reads when decoding NTLM fields.

2

What is the severity of CVE-2023-25563?

CVE-2023-25563 has a severity rating of 7.5 (High).

3

How does CVE-2023-25563 affect Gss-ntlmssp Project Gss-ntlmssp?

Gss-ntlmssp Project Gss-ntlmssp versions up to and excluding 1.2.0 are affected by CVE-2023-25563.

4

How can I fix CVE-2023-25563?

To fix CVE-2023-25563, it is recommended to update to version 1.2.0 or later of Gss-ntlmssp Project Gss-ntlmssp.

5

What are the references for CVE-2023-25563?

The references for CVE-2023-25563 are: - [GitHub Commit](https://github.com/gssapi/gss-ntlmssp/commit/97c62c6167299028d80765080e74d91dfc99efbd) - [GitHub Release](https://github.com/gssapi/gss-ntlmssp/releases/tag/v1.2.0) - [GitHub Security Advisory](https://github.com/gssapi/gss-ntlmssp/security/advisories/GHSA-jjjx-5qf7-9mgf)

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