CVE-2026-0966 (GCVE-0-2026-0966)

Vulnerability from cvelistv5 – Published: 2026-03-26 20:06 – Updated: 2026-03-27 20:01
VLAI?
Title
Libssh: buffer underflow in ssh_get_hexa() on invalid input
Summary
The API function `ssh_get_hexa()` is vulnerable, when 0-lenght input is provided to this function. This function is used internally in `ssh_get_fingerprint_hash()` and `ssh_print_hexa()` (deprecated), which is vulnerable to the same input (length is provided by the calling application). The function is also used internally in the gssapi code for logging the OIDs received by the server during GSSAPI authentication. This could be triggered remotely, when the server allows GSSAPI authentication and logging verbosity is set at least to SSH_LOG_PACKET (3). This could cause self-DoS of the per-connection daemon process.
Severity ?
6.5 (Medium)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
CWE
  • CWE-124 - Buffer Underwrite ('Buffer Underflow')
Assigner
References
Impacted products
Vendor Product Version
Red Hat Red Hat Enterprise Linux 10     cpe:/o:redhat:enterprise_linux:10
 Create a notification for this product.
Date Public ?
2026-02-10 18:47
Credits
Red Hat would like to thank Jakub Jelen (libssh), Jun Xu, Kang Yang, and Yunhang Zhang for reporting this issue.
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  • 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.
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  • 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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