CVE-2026-42010 (GCVE-0-2026-42010)

Vulnerability from cvelistv5 – Published: 2026-05-07 12:00 – Updated: 2026-05-14 22:14
VLAI?
Title
Gnutls: gnutls: authentication bypass via nul character in username
Summary
A flaw was found in gnutls. Servers configured with RSA-PSK (Rivest–Shamir–Adleman – Pre-Shared Key) wrongfully matched usernames containing a NUL character with truncated usernames. A remote attacker could exploit this by sending a specially crafted username, leading to an authentication bypass. This vulnerability allows an attacker to gain unauthorized access by circumventing the authentication process.
Severity ?
7.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
CWE
  • CWE-626 - Null Byte Interaction Error (Poison Null Byte)
Assigner
References
URL Tags
https://access.redhat.com/errata/RHSA-2026:13274 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-42010 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2467289 issue-trackingx_refsource_REDHAT
Impacted products
Date Public ?
2026-04-29 00:00
Credits
Red Hat would like to thank Joshua Rogers (AISLE Research Team) for reporting this issue.
Show details on NVD website
To clipboard 

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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

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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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • 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.



Detection rules are retrieved from Rulezet.