TODDR YAML::Syck up to 1.35 on Perl YAML File Parser token.c memory corruption

Summaryinfo

A vulnerability was found in TODDR YAML::Syck up to 1.35 on Perl. It has been rated as critical. The affected element is the function YAML::Syck of the file token.c of the component YAML File Parser. This manipulation causes memory corruption. This vulnerability is handled as CVE-2025-11683. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in TODDR YAML::Syck up to 1.35 on Perl. It has been declared as critical. Affected by this vulnerability is the function YAML::Syck of the file token.c of the component YAML File Parser. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

YAML::Syck versions before 1.36 for Perl has missing null-terminators which causes out-of-bounds read and potential information disclosure Missing null terminators in token.c leads to but-of-bounds read which allows adjacent variable to be read The issue is seen with complex YAML files with a hash of all keys and empty values.  There is no indication that the issue leads to accessing memory outside that allocated to the module.

The advisory is shared at github.com. This vulnerability is known as CVE-2025-11683 since 10/13/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 271777 (Amazon Linux 2023 : perl-YAML-Syck (ALAS2023-2025-1248)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.36 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202510-2413), Tenable (271777) and CERT Bund (WID-SEC-2025-2329). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• cPanel cPanel/WHM

Productinfo

Vendor

• TODDR

Name

• YAML::Syck

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
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31
• 1.32
• 1.33
• 1.34
• 1.35

CPE 2.3info

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CPE 2.2info

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Entryinfo

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