CVE-2026-129115 JSON::XS versions from 3.0 before 4.05 for Perl read freed stack memory when a FREEZE result's serialisation grows the Perl stack under allow_tags in encode_rv
No CVSS score yet.
JSON::XS versions from 3.0 before 4.05 for Perl read freed stack memory when a FREEZE result's serialisation grows the Perl stack under allow_tags in encode_rv.
With allow_tags, an object's FREEZE method is called in list context and each returned value is encoded through a saved Perl stack pointer. When encoding a returned value calls back into Perl, through TO_JSON under convert_blessed or another FREEZE, and that callback grows the stack, the stack is reallocated while the saved pointer still refers to the freed block.
Encoding such objects reads freed memory, and encode can return undef without an error.
- CWE
- CWE-416 Use After Free
- Published
- Assigned by
- CPANSec (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
Ask an AI about this CVE
Show the prompt
Explain CVE-2026-129115 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-129115?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-129115?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-129115 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Badge for a README or a site
An image that stays current: it is drawn from the data each time it is fetched (a host that proxies images, as GitHub does, may show its copy for a while). Markdown:
[](https://cve.bz/cve/CVE-2026-129115)
HTML:
<a href="https://cve.bz/cve/CVE-2026-129115"><img src="https://cve.bz/cve/badge/CVE-2026-129115.svg" alt="CVE-2026-129115"></a>
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| JSON-XS | from 3.0 before 4.05 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | libjson-xs-perl | no fix listed | DEBIAN-CVE-2026-129115 |
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.