Medium severity · published Sep 8, 2025
CVE-2025-40929
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
5.6
CVSS
0.5%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CP
Cpanel::JSON::XS · RURBAN
before 4.40 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-40929
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-40929
github.com
https://github.com/rurban/Cpanel-JSON-XS/commit/378236219eaa35742c3962ecbdee364903b0a1f2.patch
metacpan.org
https://metacpan.org/release/RURBAN/Cpanel-JSON-XS-4.39/source/XS.xs#L713
metacpan.org
https://metacpan.org/release/RURBAN/Cpanel-JSON-XS-4.40/changes
www.openwall.com
http://www.openwall.com/lists/oss-security/2025/09/08/1
lists.debian.org
https://lists.debian.org/debian-lts-announce/2025/09/msg00034.html
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