CVE-2026-9334
Published:June 03, 2026
Updated:August 04, 2026
Cpanel::JSON::XS versions before 4.41 for Perl allow type confusion via duplicate object keys when dupkeys_as_arrayref is enabled.
decode_hv() collapses duplicate object keys into an array reference under dupkeys_as_arrayref. The branch reached for a duplicate key tests "SvTYPE (old_value) != SVt_RV && SvTYPE (SvRV (old_value)) != SVt_PVAV", which evaluates SvRV(old_value) before establishing that old_value is a reference. When the existing value is a plain scalar rather than an array reference, a non-reference scalar is dereferenced as a reference.
A caller decoding untrusted JSON with dupkeys_as_arrayref enabled is crashed, and the incompatible access follows a pointer taken from attacker controlled scalar contents.
Affected Packages
https://github.com/rurban/Cpanel-JSON-XS.git (GITHUB):
Affected version(s) >=cpan_path/MLEHMANN/JSON-XS-0.1.tar.gz <4.41Fix Suggestion:
Update to version 4.41Related Resources (7)
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Contact UsCVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
LOW
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
LOW
Weakness Type (CWE)
Access of Resource Using Incompatible Type ('Type Confusion')
EPSS
Base Score:
0.25