CVE-2026-42010

Description

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.

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CVSS v3.1 Score

7.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N

EPSS — Exploit Prediction

0.0013

Probability of exploitation

0.31%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-626 CWE-626

Affected Products

Vendor	Product	Versions
gnu	gnutls	All
redhat	hardened_images	All
redhat	openshift_container_platform	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All

References

Advisories & Patches

https://access.redhat.com/security/cve/CVE-2026-42010 https://bugzilla.redhat.com/show_bug.cgi?id=2467289

Other References

https://access.redhat.com/errata/RHSA-2026:13274

Frequently Asked Questions

What is CVE-2026-42010? +

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. It has a CVSS v3.1 base score of 7.1 (HIGH).

How severe is CVE-2026-42010? +

CVE-2026-42010 has a CVSS v3.1 score of 7.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0013, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-42010? +

CVE-2026-42010 affects products from gnu, redhat, specifically: enterprise_linux, gnutls, hardened_images, openshift_container_platform. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-42010? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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