CVE-2026-54897: 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 have a heap use-after-free vulnerability in Oj::Doc iterators (each_value, each_child, each_leaf). This occurs when a Ruby block yields during iteration and calls doc.close or d.close, freeing the document's heap memory while the C iterator is still active. The iterator then accesses freed memory, causing a use-after-free condition. This vulnerability has been fixed in version 3.17.2.
AI Analysis
Technical Summary
CVE-2026-54897 is a use-after-free vulnerability (CWE-416) in the ohler55 oj Ruby gem before version 3.17.2. The issue arises in Oj::Doc iterators such as each_value, each_child, and each_leaf. If a Ruby block yields during iteration and calls doc.close or d.close, the underlying document's heap memory is freed while the C iterator continues running. When control returns to the iterator, it accesses the freed memory, leading to a use-after-free condition accessible from Ruby code. This vulnerability was addressed and fixed in version 3.17.2.
Potential Impact
The vulnerability allows a use-after-free condition during iteration over JSON documents, which could lead to undefined behavior such as crashes or memory corruption within the Ruby process using the oj gem. The CVSS score of 2.1 indicates a low severity impact, with local attack vector and no privileges required. There are no known exploits in the wild.
Mitigation Recommendations
Upgrade the oj Ruby gem to version 3.17.2 or later, where this use-after-free vulnerability has been fixed. No other mitigation or workaround is indicated.
CVE-2026-54897: 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 have a heap use-after-free vulnerability in Oj::Doc iterators (each_value, each_child, each_leaf). This occurs when a Ruby block yields during iteration and calls doc.close or d.close, freeing the document's heap memory while the C iterator is still active. The iterator then accesses freed memory, causing a use-after-free condition. This vulnerability has been fixed in version 3.17.2.
CVSS v4.0
Score 2.1low
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-54897 is a use-after-free vulnerability (CWE-416) in the ohler55 oj Ruby gem before version 3.17.2. The issue arises in Oj::Doc iterators such as each_value, each_child, and each_leaf. If a Ruby block yields during iteration and calls doc.close or d.close, the underlying document's heap memory is freed while the C iterator continues running. When control returns to the iterator, it accesses the freed memory, leading to a use-after-free condition accessible from Ruby code. This vulnerability was addressed and fixed in version 3.17.2.
Potential Impact
The vulnerability allows a use-after-free condition during iteration over JSON documents, which could lead to undefined behavior such as crashes or memory corruption within the Ruby process using the oj gem. The CVSS score of 2.1 indicates a low severity impact, with local attack vector and no privileges required. There are no known exploits in the wild.
Mitigation Recommendations
Upgrade the oj Ruby gem to version 3.17.2 or later, where this use-after-free vulnerability has been fixed. No other mitigation or workaround is indicated.
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: 6a446e6e27e9c79719c5090e
Added to database: 07/01/2026, 01:33:34 UTC
Last enriched: 07/01/2026, 01:37:22 UTC
Last updated: 07/01/2026, 01:51:16 UTC
Views: 3
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.