RURBAN Cpanel::JSON::XS up to 4.39 on Perl heap-based overflow

Summaryinfo

A vulnerability was found in RURBAN Cpanel::JSON::XS up to 4.39 on Perl and classified as critical. This issue affects some unknown processing. Such manipulation leads to heap-based overflow. This vulnerability is documented as CVE-2025-40929. The attack can be executed remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in RURBAN Cpanel::JSON::XS up to 4.39 on Perl and classified as critical. Affected by this issue is an unknown code. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. CVE summarizes:

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact

The advisory is shared for download at metacpan.org. This vulnerability is handled as CVE-2025-40929 since 04/16/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 264576 (Debian dsa-6000 : libcpanel-json-xs-perl - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.40 eliminates this vulnerability. Applying the patch 378236219eaa35742c3962ecbdee364903b0a1f2 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 Tenable (264576) and CERT Bund (WID-SEC-2025-2081). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• cPanel cPanel/WHM

Productinfo

Type

• Hosting Control Software

Vendor

• RURBAN

Name

• Cpanel::JSON::XS

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.18
• 4.19
• 4.20
• 4.21
• 4.22
• 4.23
• 4.24
• 4.25
• 4.26
• 4.27
• 4.28
• 4.29
• 4.30
• 4.31
• 4.32
• 4.33
• 4.34
• 4.35
• 4.36
• 4.37
• 4.38
• 4.39

License

• open-source

CPE 2.3info

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CPE 2.2info

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Entryinfo

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

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