CVE-2026-124540 JSON::XS versions before 4.05 for Perl allow stack exhaustion via nested tagged values under allow_tags in decode_tag
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JSON::XS versions before 4.05 for Perl allow stack exhaustion via nested tagged values under allow_tags in decode_tag.
With allow_tags, "(" starts a tagged value. Its tag and value are decoded recursively, and each can start another tagged value. Unlike arrays and objects, this nesting is not counted against max_depth.
A run of "(" bytes exhausts the C stack and triggers an uncatchable segmentation fault regardless of max_depth.
- CWE
- CWE-674 Uncontrolled Recursion
- 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-2026-124540 |
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)
- CAPEC-230 Serialized Data with Nested Payloads Likelihood: Medium · Severity: High
- CAPEC-231 Oversized Serialized Data Payloads Likelihood: Medium · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.