Google Go up to 1.26.0 Certificate Chain certificate validation

Summaryinfo

A vulnerability has been found in Google Go up to 1.26.0 and classified as critical. This impacts an unknown function of the component Certificate Chain Handler. Performing a manipulation results in certificate validation. This vulnerability is identified as CVE-2026-27137. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Google Go up to 1.26.0. It has been classified as problematic. This affects an unknown part of the component Certificate Chain Handler. The manipulation with an unknown input leads to a certificate validation vulnerability. CWE is classifying the issue as CWE-295. The product does not validate, or incorrectly validates, a certificate. This is going to have an impact on integrity. The summary by CVE is:

When verifying a certificate chain which contains a certificate containing multiple email address constraints which share common local portions but different domain portions, these constraints will not be properly applied, and only the last constraint will be considered.

This vulnerability is uniquely identified as CVE-2026-27137 since 02/17/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/01/2026). The attack technique deployed by this issue is T1587.003 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 301389 (Linux Distros Unpatched Vulnerability : CVE-2026-27137), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.26.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (301389) and CERT Bund (WID-SEC-2026-0548). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Amazon Linux 2
• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Golang Go

Productinfo

Type

• Programming Language Software

Vendor

• Google

Name

• Go

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26.0

License

• open-source

Website

• Vendor: https://www.google.com/

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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