Vulnerability · Published May 11, 2026 · Assigned by GitHub_M
CVE-2026-41257jq: Signed-int overflow in `stack_reallocate` (jq VM stack)
Medium 6.4
In plain English
A medium-severity integer overflow in jq from jqlang. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
jq is a command-line JSON processor. In 1.8.1 and earlier, the jq bytecode VM's data stack tracks its allocation size in a signed int. When the stack grows beyond ≈1 GiB (via deeply nested generator forks), the doubling arithmetic overflows. The wrapped value is passed to realloc and then used for a memmove with attacker-influenced offsets.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.22 | jq | 1.8.2-r0 | ALPINE-CVE-2026-41257 |
| Alpine:v3.23 | jq | 1.8.2-r0 | ALPINE-CVE-2026-41257 |
| Alpine:v3.24 | jq | 1.8.2-r0 | ALPINE-CVE-2026-41257 |
| Debian:12 | jq | 1.6-2.1+deb12u2 | DEBIAN-CVE-2026-41257 |
| Debian:13 | jq | 1.7.1-6+deb13u3 | DEBIAN-CVE-2026-41257 |
| Debian:14 | jq | 1.8.1-6 | DEBIAN-CVE-2026-41257 |
| Ubuntu:22.04:LTS | jq | no fix listed | UBUNTU-CVE-2026-41257 |
| Ubuntu:24.04:LTS | jq | no fix listed | UBUNTU-CVE-2026-41257 |
| Ubuntu:25.10 | jq | no fix listed | UBUNTU-CVE-2026-41257 |
| Ubuntu:26.04:LTS | jq | no fix listed | UBUNTU-CVE-2026-41257 |
| Ubuntu:26.10 | jq | no fix listed | UBUNTU-CVE-2026-41257 |
Affected products (as reported)
Weakness: CWE-190, CWE-787 · Vector: CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
References
- https://github.com/jqlang/jq/security/advisories/GHSA-4jm8-m363-4539 x_refsource_CONFIRM