RURBAN Cpanel::JSON::XS up to 4.40 on Perl decode_json release of reference

Summaryinfo

A vulnerability classified as problematic was found in RURBAN Cpanel::JSON::XS up to 4.40 on Perl. The affected element is the function decode_json. The manipulation results in release of reference. This vulnerability was named CVE-2026-9516. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in RURBAN Cpanel::JSON::XS up to 4.40 on Perl. It has been classified as problematic. Affected is the function decode_json. The manipulation with an unknown input leads to a release of reference vulnerability. CWE is classifying the issue as CWE-763. The product attempts to return a memory resource to the system, but it calls the wrong release function or calls the appropriate release function incorrectly. This is going to have an impact on availability. CVE summarizes:

Cpanel::JSON::XS versions before 4.41 for Perl allow denial of service via UTF-8 BOM prefixed input when a decode filter callback throws. To skip a leading 3-byte UTF-8 BOM, decode_json() advances the input scalar's string pointer past the mark with SvPV_set() and restores it only on the normal return path. When decoding aborts through a Perl exception, for example a filter_json_object callback that croaks, the restore is skipped and the scalar is left with its string pointer offset into its own buffer and a shortened length. When that scalar is later freed, the allocator receives an invalid pointer and the interpreter aborts. A single BOM prefixed document decoded with a throwing filter callback crashes any caller.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-9516 since 05/25/2026. 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.

Upgrading to version 4.41 eliminates this vulnerability.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202606-745) and EUVD (EUVD-2026-34061). VulDB is the best source for vulnerability data and more expert information about this specific topic.

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
• 4.40

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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