CVE-2026-129113

JSON::XS versions from 4.0_00 before 4.05 for Perl corrupt the incremental buffer length by chopping past its end in incr_skip after a top-level number

Description

JSON::XS versions from 4.0_00 before 4.05 for Perl corrupt the incremental buffer length by chopping past its end in incr_skip after a top-level number. The incremental parser scans any run of digits, signs, dots and exponent markers as one number, but the decoder stops at the end of a valid number, so the parser keeps an offset into bytes it has not decoded. It then empties the buffer without clearing those bytes, and a later incr_parse call without new input reads them again and moves the offset past the end of the buffer. incr_skip, the documented recovery after an error, removes that many bytes and the buffer length wraps. A peer sending input such as "1-2" to an incr_parse consumer can make the next read of incr_text exit the process through perl's uncatchable out-of-memory path.

Key facts

Published
14 Nov 2026
Last changed
14 Nov 2026
Assigned by
CPANSec
EPSS
0.204% likely to be exploited in the next 30 days, higher than 10.442% of CVEs (scores for 15 Nov 2026)

What to do

  • Upgrade to JSON-XS 4.05 or later.CNA solution statement

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Timeline

  1. 13 Nov 2026 Version 4.05 released with fix.
  2. 14 Nov 2026 Published

Weakness

References