{"id":"UBUNTU-CVE-2026-43894","details":"jq is a command-line JSON processor. In 1.8.1 and earlier, when decNumberFromString is given a number literal of INT_MAX-1 (2147483646) digits, the D2U() macro overflows during signed-int arithmetic. The wrapped negative value bypasses the heap-allocation size check, causes the function to use a 30-byte stack buffer, and then writes ≈715 million 16-bit units (≈1.4 GiB) at an offset 1.43 GiB below the stack frame. The written content is fully attacker-controlled (the parsed decimal digits, packed 3-per-unit).","modified":"2026-05-21T06:15:06.155790485Z","published":"2026-05-11T18:16:00Z","upstream":["CVE-2026-43894"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-43894"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-43894"},{"type":"REPORT","url":"https://github.com/jqlang/jq/security/advisories/GHSA-5v7p-2r57-2g4g"}],"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-2026-43894.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"}]}],"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","1.5+dfsg-1ubuntu0.1+esm4"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.5+dfsg-1ubuntu0.1+esm4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43894.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"}]}],"versions":["1.5+dfsg-2","1.5+dfsg-2ubuntu0.1~esm1","1.5+dfsg-2ubuntu0.1~esm2","1.5+dfsg-2ubuntu0.1~esm3"],"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"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43894.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"}]}],"versions":["1.5+dfsg-2build1","1.6-1","1.6-1ubuntu0.20.04.1","1.6-1ubuntu0.20.04.1+esm1","1.6-1ubuntu0.20.04.1+esm2","1.6-1ubuntu0.20.04.1+esm3"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.6-1ubuntu0.20.04.1+esm3"},{"binary_name":"libjq1","binary_version":"1.6-1ubuntu0.20.04.1+esm3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43894.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6-2.1ubuntu2","1.6-2.1ubuntu3","1.6-2.1ubuntu3.1","1.6-2.1ubuntu3.2"],"ecosystem_specific":{"binaries":[{"binary_version":"1.6-2.1ubuntu3.2","binary_name":"jq"},{"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-2026-43894.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"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","1.7.1-3ubuntu0.24.04.2"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.7.1-3ubuntu0.24.04.2"},{"binary_version":"1.7.1-3ubuntu0.24.04.2","binary_name":"libjq1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43894.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/jq?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.7.1-3ubuntu1","1.7.1-6ubuntu1","1.8.1-3ubuntu1","1.8.1-3ubuntu1.1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.8.1-3ubuntu1.1","binary_name":"jq"},{"binary_version":"1.8.1-3ubuntu1.1","binary_name":"libjq1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43894.json"}},{"package":{"name":"jq","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/jq?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.1-3ubuntu1","1.8.1-4ubuntu1","1.8.1-4ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"jq","binary_version":"1.8.1-4ubuntu2"},{"binary_name":"libjq1","binary_version":"1.8.1-4ubuntu2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43894.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}