Cpanel::JSON::XS versions before 4.80 for Perl use the parent interpreter's scalars from a parser object cloned into a new ithread
Affects Cpanel::JSON::XS before 4.80 on Perl built with ithreads (5.8.9 or later) when a parser object is created before a thread starts and then used inside that thread. CVSS rates it 8.1. Fixed in 4.80.
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Fix
- Fixed in 4.80
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: yes
- Technical impact: total
Summary
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.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: total
- Record last updated
Affected versions
- Cpanel-JSON-XS
fixed in 4.80
References 2
GitHub · rurban/Cpanel-JSON-XS
metacpan.org
Questions about CVE-2026-110681
What does this mean?
A parser object created before a new Perl thread starts can be cloned into that thread. Inside the thread, it then uses the parent interpreter's scalars.Source: github.com
Am I affected, and how do I check?
Cpanel::JSON::XS versions before 4.80 are affected. The bug needs a Perl built with ithreads (USE_ITHREADS) and Perl 5.8.9 or later, plus a parser object that is created before a thread starts and then used inside it. To check, run perl -V and look for useithreads, and run perl -MCpanel::JSON::XS -e 'print $Cpanel::JSON::XS::VERSION' to see the installed module version.Source: github.com
What should I do about it?
Upgrade Cpanel::JSON::XS to 4.80 or later, which is the fixed version.Source: github.com
Is it being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data