CVE-2026-43896 jq: Stack Overflow in Recursive Object Merge
A crafted jq program causes a stack overflow and crash in the JSON processor, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-43896?
CVE-2026-43896 is a medium-severity denial of service vulnerability in jqlang jq, published on 11 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
jq is a command-line JSON processor. In 1.8.1 and earlier, unbounded recursion in jv_object_merge_recursive() allows a crafted jq program to crash the process with a segfault. The function is reachable through the * operator when both operands are objects.
Weakness: CWE-674
Which versions are affected by CVE-2026-43896?
It affects 1 product.
Products include Jqlang Jq.
How do I fix CVE-2026-43896?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-43896 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43896 exists.
Other vulnerabilities in jqlang jq
- CVE-2026-32316 jq: Integer overflow in jvp_string_append() allows Heap-based Buffer Overflow
- CVE-2024-53427 Memory corruption in jq
- CVE-2025-48060 AddressSanitizer: stack-buffer-overflow in jq_fuzz_execute (jv_string_vfmt)
- CVE-2023-49355 Memory corruption in n/a
- CVE-2026-49839 jq --rawfile invalid-state reuse after String too long causes heap-buffer-overflow
Sources
Also known as ALPINE-CVE-2026-43896, AZL-86375, BELL-CVE-2026-43896, DEBIAN-CVE-2026-43896, ECHO-deed-a114-4949, GHSA-mg96-6h3q-g846 and 1 more.