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CVE-2026-54500 (GCVE-0-2026-54500)

Vulnerability from cvelistv5 – Published: 2026-06-30 23:08 – Updated: 2026-07-01 14:26
VLAI
Title
Oj: intern.c form_attr has an uninitialized stack read
Summary
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.3, Oj.load in :object mode reads uninitialized stack memory (and, for long keys, reads out of bounds) when parsing a JSON object whose key is 254 bytes or longer. The interned bytes can surface to the caller, disclosing process stack memory. In ext/oj/intern.c, form_attr() handles the long-key path by allocating a heap buffer, `b`, populating it with the attribute name, and then freeing it — but it passed the uninitialized stack buffer buf (not b) to rb_intern3(). rb_intern3 therefore reads len + 1 bytes of uninitialized stack memory. When the key length is >= 256, it also reads out of bounds past the 256-byte buf. The resulting bytes are interned and can reach the caller via the produced Symbol or via the EncodingError message raised on invalid UTF-8, leaking process stack contents. This issue has been fixed in version 3.17.3.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-01 13:34 UTC
CWE
  • CWE-125 - Out-of-bounds Read
  • CWE-908 - Use of Uninitialized Resource
Assigner
References
Impacted products
Vendor Product Version CPE status
ohler55 oj Affected: < 3.17.3
guessed Create a notification for this product.
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