0.0
NA
CVE-2026-77781
Tie::Hash::Regex versions before 2.0.0 for Perl will throw an exception on unparseable lookup keys
Description

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.

INFO

Published Date :

Aug. 22, 2026, 12:16 a.m.

Last Modified :

Aug. 22, 2026, 4:18 a.m.

Remotely Exploit :

No

Source :

9b29abf9-4ab0-4765-b253-1875cd9b441e
Affected Products

The following products are affected by CVE-2026-77781 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Update Tie::Hash::Regex to version 2.0.0 or later to prevent exceptions from malformed keys.
  • Update Tie::Hash::Regex to version 2.0.0 or later.
  • Avoid using unparseable keys with the module.
  • Implement input validation for lookup keys.
  • Use eval guards for regex compilation.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-77781.

URL Resource
https://github.com/davorg-cpan/tie-hash-regex/commit/4239732cb76233543e2ded8ff5e0f238af152e0c.patch
https://metacpan.org/release/DAVECROSS/Tie-Hash-Regex-2.0.0/source/Changes
http://www.openwall.com/lists/oss-security/2026/08/22/2
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-77781 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-77781 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-77781 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-77781 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Aug. 22, 2026

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2026/08/22/2
  • New CVE Received by 9b29abf9-4ab0-4765-b253-1875cd9b441e

    Aug. 22, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://github.com/davorg-cpan/tie-hash-regex', 'modules': ['Tie::Hash::Regex'], 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '2.0.0', 'versionType': 'custom'}], 'packageURL': 'pkg:cpan/Tie-Hash-Regex', 'packageName': 'Tie-Hash-Regex', 'programFiles': ['lib/Tie/Hash/Regex.pm'], 'collectionURL': 'https://cpan.org/modules', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': 'Tie::Hash::Regex::FETCH'}, {'name': 'Tie::Hash::Regex::EXISTS'}, {'name': 'Tie::Hash::Regex::DELETE'}]}]
    Added Description 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.
    Added CWE CWE-248
    Added Reference https://github.com/davorg-cpan/tie-hash-regex/commit/4239732cb76233543e2ded8ff5e0f238af152e0c.patch
    Added Reference https://metacpan.org/release/DAVECROSS/Tie-Hash-Regex-2.0.0/source/Changes
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.