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CVE-2026-54896GHSA-35W3-PJM6-WJ95

Oj: Heap Buffer Overflow in Oj.dump Exception Serialization via Large Indent

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 3.17.2, 3.17.3
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: poc
  • Automatable: no
  • Technical impact: partial

Summary

Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2, when in object mode, Oj.dump is vulnerable to a heap buffer overflow when serializing Exception objects with a large :indent value. The serializer allocates a buffer sized for the object's attributes but does not account for the indent bytes added on each write. With indent: 5000, the accumulation of 5,000-byte indent strings overflows the 13,150-byte heap allocation, corrupting adjacent heap memory. This issue has been fixed in version 3.17.2.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: poc · Automatable: no · Technical impact: partial

  3. Record last updated

Affected versions

  • ohler55 oj

    fixed in 3.17.2

  • ojRubyGems

    fixed in 3.17.3

References 1

GitHub · ohler55/oj