CVE-2026-39979

Fixed in a distro release EPSS <1%CVSS 6.9

jq is a command-line JSON processor. In commits before 2f09060afab23fe9390cce7cb860b10416e1bf5f, the jv_parse_sized() API in libjq accepts a counted buffer with an explicit length parameter, but its error-handling path formats the input buffer using %s in jv_string_fmt(), which reads until a NUL terminator is found rather than respecting the caller-supplied length. This means that when malformed JSON is passed in a non-NUL-terminated buffer, the error construction logic performs an out-of-bounds read past the end of the buffer. The vulnerability is reachable by any libjq consumer calling jv_parse_sized() with untrusted input, and depending on memory layout, can result in memory disclosure or process termination. The issue has been patched in commit 2f09060afab23fe9390cce7cb860b10416e1bf5f.

Published 2026-04-13 · CVE record · OSV

Products: jqlang jq, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On, Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.6 Telecommunications Update Service, Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions, Red Hat Enterprise Linux 8.8 Telecommunications Update Service, Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.4 Extended Update Support, Red Hat Enterprise Linux 9.6 Extended Update Support, Red Hat OpenShift Container Platform 4.12, Red Hat OpenShift Container Platform 4.13, Red Hat OpenShift Container Platform 4.14, Red Hat OpenShift Container Platform 4.15, Red Hat OpenShift Container Platform 4.16, Red Hat OpenShift Container Platform 4.17, Red Hat OpenShift Container Platform 4.18, Red Hat OpenShift Container Platform 4.19, Red Hat AI Inference Server 3.2, Red Hat AI Inference Server 3.3, Red Hat Hardened Images, Red Hat Ansible Automation Platform 2, Red Hat Ceph Storage 4

Distro releases