Description
Cpanel::JSON::XS versions before 4.80 for Perl leak the decoded key of an object rejected for a duplicate key or a missing colon in decode_hv. A quoted key of 24 or more bytes, or one containing a non-ASCII byte or an escape sequence, is decoded into a new scalar. Nothing frees that scalar when the object is rejected for a missing ':' after the key or, from 4.09, for a duplicate key. Duplicate keys are an error unless allow_dupkeys, dupkeys_as_arrayref or relaxed is set. A process that keeps running after a failed decode retains one key per rejected document, with its size chosen by the sender. Repeated requests exhaust process memory.
References2
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 42 · as of 10 November 2026
- CWE
- CWE-401
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