CVE-2026-41257 MEDIUM

CVE-2026-41257: jq: Signed-int overflow in `stack_reallocate` (jq VM stack)

Vendor Jqlang
Product jq
Weakness CWE-190
Published May 11, 2026
Last update May 11, 2026

CVSS base score

6.4/10
Attack vector Local
Attack complexity High
Privileges required None
User interaction
Confidentiality
Integrity

CVSS 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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

May 11, 2026 CVE published
May 11, 2026 Record updated