CVE-2026-124536 JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse
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JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse.
The parser appends each chunk to its buffer and compares max_size with how far it has progressed, not with the buffer length. It treats a NUL byte as the end of the input, so a NUL within the first max_size bytes keeps it short of the limit. The buffer keeps growing, and incr_skip cannot remove the NUL.
A peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size.
- CWE
- CWE-770 Allocation of Resources Without Limits or Throttling
- Published
- Assigned by
- CPANSec (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| JSON-XS | before 4.05 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | libjson-xs-perl | no fix listed | DEBIAN-CVE-2026-124536 |
From the distributions' data via OSV.dev: the Debian Security Tracker. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian.
Attack patterns (CAPEC)
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-770 (20).