CVE-2026-110681 Cpanel::JSON::XS versions before 4.80 for Perl use the parent interpreter's scalars from a parser object cloned into a new ithread.
A use-after-free vulnerability in Cpanel::JSON::XS allows attackers to cause crashes or potentially execute code via thread cloning issues.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Not stated
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-110681?
CVE-2026-110681 is an use after free vulnerability, published on 19 Oct 2026.
Official description
Cpanel::JSON::XS versions before 4.80 for Perl use the parent interpreter's scalars from a parser object cloned into a new ithread.
A parser object holds its callbacks and its incremental parse buffer as raw scalar pointers. When a thread is created, these are copied into the new interpreter unchanged, so the child's parser uses, and later frees, scalars that belong to the parent and may already have been freed there.
A parser created before a thread starts and used inside it can call freed callbacks, corrupt reference counts and crash the process.
Weakness: CWE-416
Which versions are affected by CVE-2026-110681?
How do I fix CVE-2026-110681?
Upgrade to a fixed version.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-110681 being exploited?
There is no known exploitation of CVE-2026-110681 in the wild and no public exploit code.
Sources
Also known as AZL-109869, DEBIAN-CVE-2026-110681, GHSA-rmwh-p89p-h6wq, UBUNTU-CVE-2026-110681.