CVE-2026-54896
Oj: Heap Buffer Overflow in Oj.dump Exception Serialization via Large Indent
Vexday Risk Score
8Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 2.1EPSS 0.1%KEV nãoPoC —Nuclei —Metasploit —Patch —
Lifecycle
30 Jun 2026Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
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.
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Affected products
ohler55 · ojWant to know if your infrastructure is exposed to this?
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