CVE-2026-8295: Simdjson

Medium severity, CVSS 6.9. EPSS: 0.4% chance of exploitation in the next 30 days.

An integer overflow vulnerability in the simdjson document-builder API allows incorrect buffer size calculations in "string_builder::escape_and_append()" when processing very large input strings on platforms with limited "size_t" width (e.g., 32-bit builds). The overflow can cause insufficient buffer allocation, leading to out-of-bounds memory reads in SIMD routines and potentially resulting in information disclosure, memory corruption, or malformed JSON output. This vulnerability has been fixed in 4.6.4 release

Affected products

• Simdjson Simdjson: before 4.6.4 (fixed in 4.6.4)

Published 2026-05-14. Last modified 2026-06-17.