{"id":"UBUNTU-CVE-2026-40164","details":"jq is a command-line JSON processor. Before commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784, jq used MurmurHash3 with a hardcoded, publicly visible seed (0x432A9843) for all JSON object hash table operations, which allowed an attacker to precompute key collisions offline. By supplying a crafted JSON object (~100 KB) where all keys hashed to the same bucket, hash table lookups degraded from O(1) to O(n), turning any jq expression into an O(n²) operation and causing significant CPU exhaustion. This affected common jq use cases such as CI/CD pipelines, web services, and data processing scripts, and was far more practical to exploit than existing heap overflow issues since it required only a small payload. This issue has been patched in commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784.","modified":"2026-08-31T17:16:06.436902257Z","published":"2026-04-14T00:16:00Z","related":["USN-8202-1","USN-8202-2"],"upstream":["CVE-2026-40164"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-40164"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-40164"},{"type":"REPORT","url":"https://github.com/jqlang/jq/security/advisories/GHSA-wwj8-gxm6-jc29"},{"type":"REPORT","url":"https://github.com/jqlang/jq/commit/0c7d133c3c7e37c00b6d46b658a02244fdd3c784"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8202-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8202-2"}],"affected":[{"package":{"name":"jq","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.2-8","1.3-1","1.3-1.1ubuntu1","1.3-1.1ubuntu1.1","1.3-1.1ubuntu1.1+esm3","1.3-1.1ubuntu1.1+esm4"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3-1.1ubuntu1.1+esm4","binary_name":"jq"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=esm-apps%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5+dfsg-1ubuntu0.1+esm4"}]}],"versions":["1.4-2.1","1.5+dfsg-1","1.5+dfsg-1ubuntu0.1","1.5+dfsg-1ubuntu0.1+esm2","1.5+dfsg-1ubuntu0.1+esm3"],"ecosystem_specific":{"binaries":[{"binary_version":"1.5+dfsg-1ubuntu0.1+esm4","binary_name":"jq"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5+dfsg-2ubuntu0.1~esm3"}]}],"versions":["1.5+dfsg-2","1.5+dfsg-2ubuntu0.1~esm1","1.5+dfsg-2ubuntu0.1~esm2"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.5+dfsg-2ubuntu0.1~esm3"},{"binary_name":"libjq1","binary_version":"1.5+dfsg-2ubuntu0.1~esm3"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6-1ubuntu0.20.04.1+esm2"}]}],"versions":["1.5+dfsg-2build1","1.6-1","1.6-1ubuntu0.20.04.1","1.6-1ubuntu0.20.04.1+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.6-1ubuntu0.20.04.1+esm2"},{"binary_version":"1.6-1ubuntu0.20.04.1+esm2","binary_name":"libjq1"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6-2.1ubuntu3.2"}]}],"versions":["1.6-2.1ubuntu2","1.6-2.1ubuntu3","1.6-2.1ubuntu3.1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"jq","binary_version":"1.6-2.1ubuntu3.2"},{"binary_name":"libjq1","binary_version":"1.6-2.1ubuntu3.2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.7.1-3ubuntu0.24.04.2"}]}],"versions":["1.6-3","1.7-1","1.7.1-2","1.7.1-3","1.7.1-3build1","1.7.1-3ubuntu0.24.04.1"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.7.1-3ubuntu0.24.04.2"},{"binary_name":"libjq1","binary_version":"1.7.1-3ubuntu0.24.04.2"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/jq?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.1-3ubuntu1.1"}]}],"versions":["1.7.1-3ubuntu1","1.7.1-6ubuntu1","1.8.1-3ubuntu1"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.8.1-3ubuntu1.1"},{"binary_name":"libjq1","binary_version":"1.8.1-3ubuntu1.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.1-4ubuntu2"}]}],"versions":["1.8.1-3ubuntu1","1.8.1-4ubuntu1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.8.1-4ubuntu2","binary_name":"jq"},{"binary_name":"libjq1","binary_version":"1.8.1-4ubuntu2"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40164.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}