Is there a public exploit for CVE-2026-124539?

No public exploit for CVE-2026-124539 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

— Unscored

JSON::XS versions before 4.05 for Perl leak the decoded key of an object rejected for a missing colon in decodehv.

CVE-2026-124539

JSON::XS versions before 4.05 for Perl leak the decoded key of an object rejected for a missing colon in decodehv. Unless it is short plain ASCII, a quoted key is decoded into a new scalar. Nothing frees that scalar when the object is rejected for a missing ':' after the key. 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.

Assessment

CVSS: Not yet scored
Severity: Unscored
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 14 November 2026
Last updated: 14 November 2026
Assigner: CPANSec

At the source

EUVD (ENISA)

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