Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted
Source GCVE Database
Not known to be exploited · CVSS 5.6 Medium.
Data as of 4 Nov 2026, 17:16 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 5.6 |
|---|
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 8 Sep 2025
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 4 Nov 2026.
Description
Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact
References
- nvd.nist.gov/vuln/detail/CVE-2025-40929 (opens in a new tab)
- github.com/rurban/Cpanel-JSON-XS/commit/378236219eaa35742c3962ecbdee364903b0a1f2.patch (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/09/msg00034.html (opens in a new tab)
- metacpan.org/release/RURBAN/Cpanel-JSON-XS-4.39/source/XS.xs (opens in a new tab)
- metacpan.org/release/RURBAN/Cpanel-JSON-XS-4.40/changes (opens in a new tab)
- openwall.com/lists/oss-security/2025/09/08/1 (opens in a new tab)