Tie::Hash::Regex up to 1.x Regular Expression Compilation FETCH/EXISTS/DELETE input validation

Summaryinfo

A vulnerability was found in Tie::Hash::Regex up to 1.x and classified as problematic. Affected is the function FETCH/EXISTS/DELETE of the component Regular Expression Compilation. The manipulation results in input validation. This vulnerability is reported as CVE-2026-77781. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability classified as problematic has been found in Tie::Hash::Regex up to 1.x. Affected is the function FETCH/EXISTS/DELETE of the component Regular Expression Compilation. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on availability. CVE summarizes:

Tie::Hash::Regex versions before 2.0.0 for Perl will throw an exception on unparseable lookup keys. The FETCH, EXISTS and DELETE methods throw an exception when on malformed regular expressions. Each method falls back to a regex match when the key is not already stored in the hash, compiling the caller's key with a bare qr// and no eval guard. A key that is not a valid regular expression pattern, such as a single unmatched bracket, dies. An application that looks up externally supplied strings in a tied hash will die on an invalid key.

The advisory is shared for download at metacpan.org. This vulnerability is traded as CVE-2026-77781 since 08/21/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 338843 (Linux Distros Unpatched Vulnerability : CVE-2026-77781), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.0.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (338843) and EUVD (EUVD-2026-64205). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

• Tie::Hash::Regex

Version

• 1.x

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• 🔒

CPE 2.2info

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VulDB is the best source for vulnerability data and more expert information about this specific topic.

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