CVE-2026-54898: CWE-416: Use After Free in ohler55 oj
Oj (Optimized JSON) is a Ruby gem for JSON parsing and object marshalling. Versions prior to 3.17.2 contain a use-after-free vulnerability in the Oj::Parser#parse method when a SAJ/SAJ2 callback mutates the input JSON string during parsing. This occurs because the C parser holds a raw pointer to the Ruby string's internal buffer, which can be reallocated and freed if the string is resized during a callback. The issue has been fixed in version 3.17.2.
AI Analysis
Technical Summary
CVE-2026-54898 is a use-after-free vulnerability in the Oj Ruby gem's C parser engine. When a SAJ/SAJ2 callback mutates the input JSON string during parsing, such as by resizing it with String#replace, the Ruby string buffer may be reallocated and the old buffer freed. The parser's raw pointer then becomes dangling, leading to a use-after-free condition at parser.c:607. This vulnerability affects all versions prior to 3.17.2 and has been resolved in 3.17.2.
Potential Impact
The vulnerability could lead to a heap use-after-free condition during JSON parsing if the input string is mutated in a callback. This may cause undefined behavior, including potential crashes or memory corruption. The CVSS 4.0 score is 2.1 (low severity), indicating limited impact and requiring local access with low complexity to exploit.
Mitigation Recommendations
Upgrade to version 3.17.2 or later, where this use-after-free vulnerability has been fixed. No other mitigation is indicated or required.
CVE-2026-54898: CWE-416: Use After Free in ohler55 oj
Description
Oj (Optimized JSON) is a Ruby gem for JSON parsing and object marshalling. Versions prior to 3.17.2 contain a use-after-free vulnerability in the Oj::Parser#parse method when a SAJ/SAJ2 callback mutates the input JSON string during parsing. This occurs because the C parser holds a raw pointer to the Ruby string's internal buffer, which can be reallocated and freed if the string is resized during a callback. The issue has been fixed in version 3.17.2.
CVSS v4.0
Score 2.1low
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-54898 is a use-after-free vulnerability in the Oj Ruby gem's C parser engine. When a SAJ/SAJ2 callback mutates the input JSON string during parsing, such as by resizing it with String#replace, the Ruby string buffer may be reallocated and the old buffer freed. The parser's raw pointer then becomes dangling, leading to a use-after-free condition at parser.c:607. This vulnerability affects all versions prior to 3.17.2 and has been resolved in 3.17.2.
Potential Impact
The vulnerability could lead to a heap use-after-free condition during JSON parsing if the input string is mutated in a callback. This may cause undefined behavior, including potential crashes or memory corruption. The CVSS 4.0 score is 2.1 (low severity), indicating limited impact and requiring local access with low complexity to exploit.
Mitigation Recommendations
Upgrade to version 3.17.2 or later, where this use-after-free vulnerability has been fixed. No other mitigation is indicated or required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-16T13:49:33.555Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
- Gcve Source
- db.gcve.eu
Threat ID: 6a446e6e27e9c79719c5090b
Added to database: 07/01/2026, 01:33:34 UTC
Last enriched: 07/01/2026, 01:37:28 UTC
Last updated: 07/01/2026, 01:51:17 UTC
Views: 3
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