CVE-2026-124539: JSON::XS versions before 4.05 for Perl leak the decoded key of an object rejected for a missing
Source GCVE Database
Not known to be exploited : upgrade to 4.05 when convenient.
Data as of 14 Nov 2026, 13:18 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in 4.05
Exploitation evidence
Disclosed: evidence found.
CVE published 14 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 14 Nov 2026.
What to do
Upgrade JSON-XS (Perl module) to 4.05.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| JSON-XS | Affected
| Fixed in
|
CPANJSON-XSpkg:cpan/JSON-XSOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in JSON::XS version 4.05 and later. Users should upgrade to version 4.05 or newer to resolve this memory leak issue. No other mitigation is indicated.
Description
JSON::XS versions before 4.05 for Perl have a memory leak vulnerability in the decode_hv function. When decoding an object with a missing colon after a key, the decoded key scalar is not freed if the object is rejected. This causes a process that continues running after failed decodes to retain one key per rejected document, potentially exhausting memory over time.