A regression in the USN-8202-1 security update for `jq` on Ubuntu 18.04 LTS and 20.04 LTS has been corrected with USN-8202-3. The original vulnerabilities, including multiple memory safety issues in string handling and type checking (CVE-2026-32316 CVSS 8.2, CVE-2026-33948 CVSS 5.3, and others), could lead to denial of service, arbitrary code execution, or information disclosure. The affected software versions are jqlang jq up to and including 1.8.1, with fixes provided in the updated Ubuntu packages.
USN-8202-1 fixed vulnerabilities in jq. The update caused a regression for Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. This update fixes the problem. We apologize for the inconvenience. Original advisory details: It was discovered that jq did not correctly handle certain string concatenations. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This issue was addressed in Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-32316) It was discovered that jq did not correctly handle recursion in certain circumstances. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-33947) It was discovered that jq did not correctly handle improperly terminated strings. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This issue was addressed in Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-33948) It was discovered that jq did not correctly handle checking certain variable types. An attacker could possibly use this issue to cause a denial of service or leak sensitive information. This issue was addressed in Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-39956) It was discovered that jq did not correctly handle certain string formatting. An attacker could possibly use this issue to leak sensitive information or cause a denial of service. (CVE-2026-39979) It was discovered that jq used a fixed seed for hash table operations. An attacker could possibly use this issue to cause a denial of service. This issue was addressed in Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-40164)