CVE-2026-124541 JSON::XS versions before 4.05 for Perl leak the decoded part of a rejected long string in decode_str
No CVSS score yet.
JSON::XS versions before 4.05 for Perl leak the decoded part of a rejected long string in decode_str.
A string is decoded through a fixed-size buffer (16 KiB in 4.04), and each time the buffer fills its contents move into a new scalar. Nothing frees that scalar when the string is then rejected for a control character, an invalid escape, malformed UTF-8 or the end of the input.
A process that keeps running after a failed decode retains the decoded part of each rejected string, with its size chosen by the sender. Repeated requests exhaust process memory.
- CWE
- CWE-401 Missing Release of Memory after Effective Lifetime
- 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-2026-124541 |
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.