CVE-2026-42010

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.

Affected Software

VendorProductVersion RangeStatus
Red HatRed Hat Enterprise Linux 100:3.8.10-4.el10_2 < *unaffected
Red HatRed Hat Enterprise Linux 10.0 Extended Update Support0:3.8.9-9.el10_0.19 < *unaffected
Red HatRed Hat Enterprise Linux 80:3.6.16-8.el8_10.6 < *unaffected
Red HatRed Hat Enterprise Linux 80:3.6.16-8.el8_10.6 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support0:3.6.14-10.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support0:4.13-3.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On0:3.6.14-10.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On0:4.13-3.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support0:3.6.16-5.el8_6.5 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support0:4.13-3.el8_6.2 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On0:3.6.16-5.el8_6.5 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On0:4.13-3.el8_6.2 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Service0:3.6.16-7.el8_8.4 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Service0:4.13-4.el8_8.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutions0:3.6.16-7.el8_8.4 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutions0:4.13-4.el8_8.1 < *unaffected
Red HatRed Hat Enterprise Linux 90:3.8.10-4.el9_8 < *unaffected
Red HatRed Hat Enterprise Linux 90:3.8.10-4.el9_8 < *unaffected
Red HatRed Hat Enterprise Linux 9.4 Update Services for SAP Solutions0:3.8.3-4.el9_4.6 < *unaffected
Red HatRed Hat Enterprise Linux 9.6 Extended Update Support0:3.8.3-6.el9_6.4 < *unaffected
Red HatRed Hat Discovery 21782159791 < *unaffected
Red HatRed Hat Discovery 21782166952 < *unaffected
Red HatRed Hat Hardened Images3.8.13-1.hum1 < *unaffected
Red HatRed Hat Update Infrastructure 51781525684 < *unaffected
Red HatRed Hat Update Infrastructure 51781525671 < *unaffected
Red HatRed Hat Update Infrastructure 51781525693 < *unaffected
Red HatRed Hat Update Infrastructure 51781525739 < *unaffected

Weaknesses

  • CWE-170: Improper Null Termination

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

gnutls: gnutls: Authentication Bypass via NUL Character in Username

Additional References

References