CVE-2026-88358

simdjson 4.6.1 contains a one-byte out-of-bounds read vulnerability in dom::parser::parse_unpadded(). A specially crafted truncated JSON document whose final structural token closes a nested array or object can cause json_iterator::walk_document() to access buf[len] after the input buffer has been exhausted. This results in a heap out-of-bounds read and may cause application termination, leading to denial of service.

• https://github.com/simdjson/simdjson/commit/20b28712ffce8320237b75a587d35a2e89140577
• https://github.com/simdjson/simdjson/issues/2815
• https://github.com/simdjson/simdjson/pull/2817
• https://github.com/simdjson/simdjson/issues/2815