Bug 2495753 (CVE-2026-54899)

Summary: CVE-2026-54899 oj: Oj: Use-After-Free in parser symbol key cache toggle
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: eshamard, jvasik, kaycoth, rblanco
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in Oj (Optimized JSON), a Ruby gem for parsing JSON. When a `Oj::Parser` instance is reused and its `symbol_keys` setting is toggled from true to false, a heap use-after-free vulnerability occurs. This happens because the internal key cache is freed but its pointer is not cleared, allowing subsequent parse operations to read from freed memory. This can lead to unpredictable application behavior, crashes, or potentially arbitrary code execution.
 Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-07-01 00:16:09 UTC 
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.