CVE-2026-0821 quickjs-ng quickjs quickjs.c js_typed_array_constructor heap-based overflow
A heap-based buffer overflow in the quickjs-ng JavaScript engine allows remote attackers to execute arbitrary code or cause denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-0821?
CVE-2026-0821 is a medium-severity memory corruption vulnerability in quickjs-ng quickjs, published on 10 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability was determined in quickjs-ng quickjs up to 0.11.0. This vulnerability affects the function js_typed_array_constructor of the file quickjs.c. Executing a manipulation can lead to heap-based buffer overflow. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized. This patch is called c5d80831e51e48a83eab16ea867be87f091783c5. A patch should be applied to remediate this issue.
Which versions are affected by CVE-2026-0821?
It affects 1 product.
Products include Quickjs-Ng Quickjs.
How do I fix CVE-2026-0821?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-0821 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-0821 exists.
Other vulnerabilities in quickjs-ng quickjs
- CVE-2025-46688 Memory corruption in QuickJS
- CVE-2026-1144 quickjs-ng quickjs Atomics Ops quickjs.c use after free
- CVE-2026-1145 quickjs-ng quickjs quickjs.c js_typed_array_constructor_ta heap-based overflow
- CVE-2026-0822 quickjs-ng quickjs quickjs.c js_typed_array_sort heap-based overflow
- CVE-2024-13903 quickjs-ng QuickJS qjs quickjs.c JS_GetRuntime stack-based overflow
Sources
Also known as ALPINE-CVE-2026-0821, DEBIAN-CVE-2026-0821, GHSA-rcpp-qhfh-r47v, UBUNTU-CVE-2026-0821.