CVE-2026-54899
Oj: Use-After-Free in Oj::Parser Symbol Key Cache Toggle
Vexday Risk Score
13Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 6.3EPSS 0.4%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. Prior to version 3.17.2, disabling symbol_keys on a reused Oj::Parser instance triggers a heap use-after-free. When symbol_keys is toggled from true to false, opt_symbol_keys_set frees the internal key cache (cache_free) but does not clear the pointer. The next parse call reads from the freed cache via cache_intern, producing a use-after-free. This issue has been fixed in version 3.17.2.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N
Affected products
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