CVE-2026-54899
Description
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.
Statement
Red Hat's only product shipping the Oj Ruby gem (Compliance Backend) already includes version 3.17.3, which contains the fix for this vulnerability. No Red Hat products are affected.
Mitigation
Upgrade the oj Ruby gem to version 3.17.2 or later.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If the expired pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If the expired pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.
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