Input chunking changes decoded numbers in Cpanel::JSON::XS incr_parse
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.
Summary
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. Top-level numbers have no closing delimiter, so the incremental parser decodes whatever has arrived, and the same bytes can yield different values depending on how reads split them (CWE-436). A peer that can influence read boundaries can change how many messages a stream consumer decodes and what values they carry.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | Cpanel-JSON-XS | 4.42 to before 4.80 | 4.80 | Patch available | CNA |
- Cpanel-JSON-XS Vendor— Affected 4.42 to before 4.80 Fixed in 4.80 Patch available CNA
Remediation
Upgrade Cpanel-JSON-XS to version 4.80 or later.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
- Fix · CNA Cpanel-JSON-XS Fixed in 4.80
Vendor assessments
Timeline
- 2026-10-20 Threatist record created from CVE-2026-110682
- 2026-10-20 Alias added: GHSA-vg22-xr3v-rw3m
- 2026-10-20 Affected versions changed · Red Hat
- 2026-10-20 CVSS score added · Red Hat
- 2026-10-21 CVSS score changed · Red Hat
- 2026-10-29 CVSS score added · CISA ADP
- 2026-10-29 CISA SSVC decision points changed
References
Sources
- CVE-2026-110682 · CVE Program
- CVE-2026-110682 · NVD
- FIRST EPSS
- GHSA-vg22-xr3v-rw3m · GitHub Advisory Database · CC BY 4.0
- CVE-2026-110682 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences