CVE-2026-54899: 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 us

unknownCVE-2026-54899

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.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: unknown
Published: 2026-07-01
Last updated: 2026-07-01
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-54899

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-548990.43% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-54899	coverage & exploitation status	NVD · CVE.org

CVE-2026-54899: 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 us

Details

Exploitation outlook

Referenced CVEs

More from NVD Recent CVEs