CVE-2026-54897: low-severity vulnerability in ohler55 oj
Oj : Use-After-Free in Oj::Doc Iterators via Reentrant Close
Published · Updated
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 2.1epss 0.1%
exploitation probability
0.1%top 96% of all CVEs
observed exploitation
nono source reports it
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to 3.17.2, Oj::Doc iterators (each_value, each_child, each_leaf) were vulnerable to a heap use-after-free. When a Ruby block yielded during iteration calls doc.close or d.close, the document's heap memory is freed while the C iterator is still running. When control returns from the block, the iterator reads from the freed region, producing a use-after-free accessible from pure Ruby. 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 · ojRelated CVEs — ohler55 oj
In the same product, most dangerous first.
CVE-2026-54900MEDIUMOj: Negative-Size memcpy in Oj::Parser create_id Attribute HandlingEPSS 0.4%CVE-2026-54902MEDIUMOj: Use-After-Free in Oj::Parser SAJ Long Key CallbackEPSS 0.4%CVE-2026-54502MEDIUMOj: Stack Buffer Overflow in Oj.dump via Large IndentEPSS 0.3%CVE-2026-54903MEDIUMOj: Integer Overflow in Oj.load 2GB String HandlingEPSS 0.3%CVE-2026-54901MEDIUMOj: Use-After-Free in Oj::Parser array_class/hash_class GC MarkingEPSS 0.3%CVE-2026-54899MEDIUMOj: Use-After-Free in Oj::Parser Symbol Key Cache ToggleEPSS 0.3%