CVE-2026-32316 jq: Integer overflow in jvp_string_append() allows Heap-based Buffer Overflow
An integer overflow in jq allows heap buffer overflows when processing large strings, potentially leading to crashes or code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-32316?
CVE-2026-32316 is a high-severity vulnerability in jqlang jq, published on 13 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
jq is a command-line JSON processor. An integer overflow vulnerability exists through version 1.8.1 within the jvp_string_append() and jvp_string_copy_replace_bad functions, where concatenating strings with a combined length exceeding 2^31 bytes causes a 32-bit unsigned integer overflow in the buffer allocation size calculation, resulting in a drastically undersized heap buffer. Subsequent memory copy operations then write the full string data into this undersized buffer, causing a heap buffer overflow classified as CWE-190 (Integer Overflow) leading to CWE-122 (Heap-based Buffer Overflow). Any system evaluating untrusted jq queries is affected, as an attacker can crash the process or potentially achieve further exploitation through heap corruption by crafting queries that produce extremely large strings. The root cause is the absence of string size bounds checking, unlike arrays and objects which already have size limits. The issue has been addressed in commit e47e56d226519635768e6aab2f38f0ab037c09e5.
Which versions are affected by CVE-2026-32316?
It affects 1 product.
Products include Jqlang Jq.
How do I fix CVE-2026-32316?
Apply the vendor's patch.
Is CVE-2026-32316 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32316 exists.
Other vulnerabilities in jqlang jq
- 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
- CVE-2026-54679 jq: potential integer overflow in jvp_string_append
Sources
Also known as ALPINE-CVE-2026-32316, AZL-82922, BELL-CVE-2026-32316, CLSA-2026-1777322146, DEBIAN-CVE-2026-32316, ECHO-a148-c5c1-3e42 and 3 more.