Vulnerability · Published Oct 19, 2026 · Assigned by CPANSec
CVE-2026-110678Cpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by buffering incremental input past max_size in incr_parse
High 7.5
In plain English
A high-severity resource allocation without limits 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 0.5% (higher than 42% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Cpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by buffering incremental input past max_size in incr_parse. The parser appends each chunk to its buffer. In scalar or list context, it compares max_size with how far it has progressed, not with the buffer length. A chunk that starts with a NUL byte stops the parser before it progresses, and a call in void context skips the check, so the buffer grows without limit. A peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libcpanel-json-xs-perl | no fix listed | DEBIAN-CVE-2026-110678 |
| Debian:13 | libcpanel-json-xs-perl | no fix listed | DEBIAN-CVE-2026-110678 |
| Debian:14 | libcpanel-json-xs-perl | 4.80-1 | DEBIAN-CVE-2026-110678 |
| Ubuntu:22.04:LTS | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110678 |
| Ubuntu:24.04:LTS | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110678 |
| Ubuntu:26.04:LTS | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110678 |
| Ubuntu:26.10 | libcpanel-json-xs-perl | no fix listed | UBUNTU-CVE-2026-110678 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cpanel-JSON-XS | 0 – before 4.80 |
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H