Process crash via reentrant iterator close
Published Jun 30, 2026 · Updated Jun 30, 2026
Use-after-free in Oj before 3.17.2 allows local users to crash a Ruby process by closing a document from an iterator block. In each_value, each_child, and each_leaf, rb_yield permits close to free the backing buffer before the C loop reads the next node. Exploitation requires Ruby code to run during the iterator callback; the published assessment bounds the resulting impact to limited service interruption.
Summary
What happened
Use-after-free in Oj before 3.17.2 allows local users to crash a Ruby process by closing a document from an iterator block. In each_value, each_child, and each_leaf, rb_yield permits close to free the backing buffer before the C loop reads the next node. Exploitation requires Ruby code to run during the iterator callback; the published assessment bounds the resulting impact to limited service interruption.
The record
- CVE
- CVE-2026-54897
- Published
- Jun 30, 2026
- Updated
- Jun 30, 2026
- Vendor
- Peter Ohler
- Product
- Oj
- Classifications
- CWE-416, T1499
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 30, 2026CVE publishedPublication date reported by the CVE source.
- Jun 30, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 3.17.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Oj::Doc iterator reentrant-close reproducerproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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