MicroQuickJS before commit 99eed3f Out-of-Bounds Read in build_backtrace

Advisories

MicroQuickJS before commit 99eed3f Out-of-Bounds Read in build_backtrace

Severity: medium
Date: 11/15/2026
Affecting: mquickjs >= 0, < 99eed3f94cb66ea7e02fd3472ca7374dee31bb89
CVE: CVE-2025-71470
CWE: CWE-125 Out-of-bounds Read
CVSS: 6.8
CVSS V4 Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References: https://github.com/bellard/mquickjs/issues/24
https://github.com/bellard/mquickjs/commit/99eed3f94cb66ea7e02fd3472ca7374dee31bb89
https://github.com/sigdevel/pocs/blob/main/res/mquickjs/1/mquickjs_c_3981
Credit: Alexander A. Shvedov (sigdevel), Fabrice Bellard
Description: MicroQuickJS (mquickjs) before commit 99eed3f contains an out-of-bounds read vulnerability because JS_Call() raises exceptions during frame setup without updating ctx->sp and ctx->fp. Attackers can supply JavaScript that calls a non-function value, causing build_backtrace() to walk stale frame pointers and crash the engine for denial of service.

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