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2970 articles · 185100 vulns · 37/41 feeds (7d)
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CVE-2026-54898PATCHED
rubygems · oj

Oj: Use-After-Free in Oj::Parser SAJ Callback via Input Mutation

Description

Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2,Oj::Parser#parse is vulnerable to a heap use-after-free when a SAJ/SAJ2 callback mutates the input JSON string during parsing. The C engine holds a raw const byte * pointer into the Ruby string's internal buffer. If a callback (e.g. hash_start) resizes the string — for example by calling String#replace with a longer value — Ruby reallocates the string buffer and frees the old one. The C parser's pointer is left dangling; the next character read at parser.c:607 is a use-after-free. This issue has been fixed in version 3.17.2.

Affected Products

VendorProductVersions
rubygemsoj< 3.17.2

References

  • https://github.com/ohler55/oj/security/advisories/GHSA-q2gm-54r6-8fwm(x_refsource_CONFIRM)

Related News (2 articles)

Tier B
CERT-FR9d ago
Multiples vulnérabilités dans les produits IBM (31 juillet 2026)
→ No new info (linked only)
Tier C
VulDB38d ago
CVE-2026-54898 | ohler55 oj up to 3.17.1 parser.c Oj::Parser#parse use after free (GHSA-q2gm-54r6-8fwm)
→ No new info (linked only)
CISA KEV❌ No
Actively exploited❌ No
Patch available
oj@3.17.3
CWECWE-416
PublishedJun 19, 2026
Last enriched38d agov2
Tags
GHSA-q2gm-54r6-8fwmrubygems
Trending Score13
Source articles2
Independent2
Info Completeness8/14
Missing: cvss, epss, kev, exploit, iocs, mitre_attack

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Verification

State: unverified
Confidence: 0%

Vulnerability Timeline

CVE Published
Jun 19, 2026
Discovered by ZDM
Jun 19, 2026
Updated: description, affectedVersions, severity
Jul 1, 2026
Patch Available
Jul 1, 2026

Version History

v2
Last enriched 38d ago
v2Tier C38d ago

Updated vendor to ohler55, product to oj, severity to CRITICAL, and affected versions to < 3.17.1, while also providing a new description.

descriptionaffectedVersionsseverity
via VulDB
v150d ago

Initial creation