CVE-2026-54899: CWE-416: Use After Free in ohler55 oj
A use-after-free vulnerability exists in the oj Ruby gem (Optimized JSON) prior to version 3.17.2. This occurs when the symbol_keys option is disabled on a reused Oj::Parser instance, leading to a heap use-after-free condition. The issue is fixed in version 3.17.2.
AI Analysis
Technical Summary
CVE-2026-54899 describes a heap use-after-free vulnerability in the oj Ruby gem before version 3.17.2. When the symbol_keys option is toggled from true to false on a reused Oj::Parser instance, the internal key cache is freed but the pointer is not cleared. Subsequent parse calls access the freed cache, causing a use-after-free condition. This vulnerability is classified as CWE-416 (Use After Free) and has a CVSS 4.0 score of 6.3 (medium severity). The issue has been resolved in oj version 3.17.2.
Potential Impact
Exploitation of this vulnerability could lead to memory corruption due to use-after-free, potentially causing application crashes or other undefined behavior. The CVSS score indicates a medium severity with network attack vector and low complexity, but requires partial attack complexity and no privileges or user interaction.
Mitigation Recommendations
Upgrade oj to version 3.17.2 or later, where this use-after-free vulnerability is fixed. No other mitigation is indicated or required according to the available data.
CVE-2026-54899: CWE-416: Use After Free in ohler55 oj
Description
A use-after-free vulnerability exists in the oj Ruby gem (Optimized JSON) prior to version 3.17.2. This occurs when the symbol_keys option is disabled on a reused Oj::Parser instance, leading to a heap use-after-free condition. The issue is fixed in version 3.17.2.
CVSS v4.0
Score 6.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-54899 describes a heap use-after-free vulnerability in the oj Ruby gem before version 3.17.2. When the symbol_keys option is toggled from true to false on a reused Oj::Parser instance, the internal key cache is freed but the pointer is not cleared. Subsequent parse calls access the freed cache, causing a use-after-free condition. This vulnerability is classified as CWE-416 (Use After Free) and has a CVSS 4.0 score of 6.3 (medium severity). The issue has been resolved in oj version 3.17.2.
Potential Impact
Exploitation of this vulnerability could lead to memory corruption due to use-after-free, potentially causing application crashes or other undefined behavior. The CVSS score indicates a medium severity with network attack vector and low complexity, but requires partial attack complexity and no privileges or user interaction.
Mitigation Recommendations
Upgrade oj to version 3.17.2 or later, where this use-after-free vulnerability is fixed. No other mitigation is indicated or required according to the available data.
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
Threat ID: 6a45260e27e9c79719982d48
Added to database: 07/01/2026, 14:37:02 UTC
Last enriched: 07/01/2026, 14:52:59 UTC
Last updated: 07/01/2026, 14:52:59 UTC
Views: 3
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