CVE-2023-25563

GSS-NTLMSSP vulnerable to multiple out-of-bounds reads when decoding NTLM fields

Description

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 `gss_accept_sec_context` 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.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.07%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: gssapi gss-ntlmssp
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-25563?
CVE-2023-25563 has been scored as a medium severity vulnerability.
How to fix CVE-2023-25563?
To fix CVE-2023-25563, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-25563 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-25563 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-25563?
CVE-2023-25563 affects gssapi gss-ntlmssp.
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