CGI::Carp up to 4.x warningsToBrowser lib/CGI/Carp.pm buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.1$0-$5k0.37+

Summaryinfo

A vulnerability categorized as problematic has been discovered in CGI::Carp up to 4.x. Affected by this vulnerability is an unknown functionality of the file lib/CGI/Carp.pm of the component warningsToBrowser. The manipulation results in buffer overflow. This vulnerability is cataloged as CVE-2026-120634. The attack may be launched remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in CGI::Carp up to 4.x. Affected is an unknown functionality of the file lib/CGI/Carp.pm of the component warningsToBrowser. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality. CVE summarizes:

CGI::Carp versions before 5.00 for Perl leak warnings across requests in persistent environments via the warningsToBrowser buffer. Warnings are held in a package-level buffer until warningsToBrowser writes them into the page as HTML comments, and the buffer is never cleared between requests. Under mod_perl, FastCGI or PSGI, warnings from one request are written into a later one. Warnings that contain one user's request data can appear in the HTML sent to another user.

The advisory is available at metacpan.org. This vulnerability is traded as CVE-2026-120634 since 11/02/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

Upgrading to version 5.00 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CGI::Carp 5.00

Timelineinfo

11/02/2026 CVE reserved
11/04/2026 +2 days Advisory disclosed
11/04/2026 +0 days VulDB entry created
11/04/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: metacpan.org
Status: Confirmed

CNA: CPANSec
CVE: CVE-2026-120634 (🔒)

GCVE (CVE): GCVE-0-2026-120634
GCVE (VulDB): GCVE-100-430914

Entryinfo

Created: 11/04/2026 01:12
Changes: 11/04/2026 01:12 (54)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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