Vulnerability · Published Oct 19, 2026 · Assigned by CPANSec
CVE-2026-110682Cpanel::JSON::XS versions from 4.42 before 4.80 for Perl let input chunking change the decoded value of top-level numbers in incr_parse
High 7.5
In plain English
A high-severity security flaw in Cpanel-JSON-XS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Cpanel::JSON::XS versions from 4.42 before 4.80 for Perl let input chunking change the decoded value of top-level numbers in incr_parse. allow_nonref is enabled by default and incr_parse inherits it. A top-level number, true, false or null has no closing delimiter, so the incremental parser decodes whatever has arrived. The bytes 12 decode as one value when read together, but as 1 and then 2 when split across two reads. A peer that can influence read boundaries can change how many messages a stream consumer decodes and what values they carry.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libcpanel-json-xs-perl | no fix listed | DEBIAN-CVE-2026-110682 |
| Debian:13 | libcpanel-json-xs-perl | no fix listed | DEBIAN-CVE-2026-110682 |
| Debian:14 | libcpanel-json-xs-perl | 4.80-1 | DEBIAN-CVE-2026-110682 |
| Ubuntu:22.04:LTS | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110682 |
| Ubuntu:24.04:LTS | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110682 |
| Ubuntu:26.04:LTS | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110682 |
| Ubuntu:26.10 | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110682 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cpanel-JSON-XS | 4.42 – before 4.80 |
Weakness: CWE-436 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N