{"id":"UBUNTU-CVE-2026-78002","details":"A flaw was found in rsyslog. An unauthenticated remote attacker can trigger a heap buffer overflow in the RainerScript `replace()` function by sending specially crafted syslog messages. This vulnerability arises from an incorrect buffer size calculation during string replacement, causing memory corruption. Successful exploitation can lead to a denial of service (DoS) for the affected system.","modified":"2026-09-21T21:40:25.866154161Z","published":"2026-08-27T17:20:00Z","related":["USN-8786-1"],"upstream":["CVE-2026-78002"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-78002"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-78002"},{"type":"REPORT","url":"https://github.com/rsyslog/rsyslog/security/advisories/GHSA-g72f-gc6v-f2w3"},{"type":"REPORT","url":"https://github.com/rsyslog/rsyslog/pull/7525"},{"type":"REPORT","url":"https://www.openwall.com/lists/oss-security/2026/08/29/1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8786-1"}],"affected":[{"package":{"name":"rsyslog","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/rsyslog?arch=source&distro=esm-infra-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.16.0-1ubuntu3.1+esm3"}]}],"versions":["8.12.0-1ubuntu2","8.12.0-1ubuntu3","8.14.0-2ubuntu1","8.14.0-2ubuntu2","8.16.0-1ubuntu1","8.16.0-1ubuntu2","8.16.0-1ubuntu3","8.16.0-1ubuntu3.1","8.16.0-1ubuntu3.1+esm1","8.16.0-1ubuntu3.1+esm2"],"ecosystem_specific":{"binaries":[{"binary_name":"rsyslog","binary_version":"8.16.0-1ubuntu3.1+esm3"},{"binary_name":"rsyslog-elasticsearch","binary_version":"8.16.0-1ubuntu3.1+esm3"},{"binary_name":"rsyslog-gnutls","binary_version":"8.16.0-1ubuntu3.1+esm3"},{"binary_name":"rsyslog-gssapi","binary_version":"8.16.0-1ubuntu3.1+esm3"},{"binary_name":"rsyslog-mysql","binary_version":"8.16.0-1ubuntu3.1+esm3"},{"binary_name":"rsyslog-pgsql","binary_version":"8.16.0-1ubuntu3.1+esm3"},{"binary_version":"8.16.0-1ubuntu3.1+esm3","binary_name":"rsyslog-relp"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-78002.json"}},{"package":{"name":"rsyslog","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/rsyslog?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.32.0-1ubuntu4.2+esm1"}]}],"versions":["8.16.0-1ubuntu9","8.16.0-1ubuntu10","8.32.0-1ubuntu3","8.32.0-1ubuntu4","8.32.0-1ubuntu4.2"],"ecosystem_specific":{"binaries":[{"binary_version":"8.32.0-1ubuntu4.2+esm1","binary_name":"rsyslog"},{"binary_version":"8.32.0-1ubuntu4.2+esm1","binary_name":"rsyslog-czmq"},{"binary_version":"8.32.0-1ubuntu4.2+esm1","binary_name":"rsyslog-elasticsearch"},{"binary_version":"8.32.0-1ubuntu4.2+esm1","binary_name":"rsyslog-gnutls"},{"binary_name":"rsyslog-gssapi","binary_version":"8.32.0-1ubuntu4.2+esm1"},{"binary_name":"rsyslog-hiredis","binary_version":"8.32.0-1ubuntu4.2+esm1"},{"binary_version":"8.32.0-1ubuntu4.2+esm1","binary_name":"rsyslog-kafka"},{"binary_version":"8.32.0-1ubuntu4.2+esm1","binary_name":"rsyslog-mongodb"},{"binary_name":"rsyslog-mysql","binary_version":"8.32.0-1ubuntu4.2+esm1"},{"binary_version":"8.32.0-1ubuntu4.2+esm1","binary_name":"rsyslog-pgsql"},{"binary_name":"rsyslog-relp","binary_version":"8.32.0-1ubuntu4.2+esm1"}],"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-2026-78002.json"}},{"package":{"name":"rsyslog","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/rsyslog?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.2001.0-1ubuntu1.3+esm1"}]}],"versions":["8.1901.0-1ubuntu4","8.2001.0-1ubuntu1","8.2001.0-1ubuntu1.1","8.2001.0-1ubuntu1.3"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro (Infra-only): 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subscription required","binaries":[{"binary_name":"rsyslog","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-czmq","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-elasticsearch","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-gnutls","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-gssapi","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-hiredis","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-kafka","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-kubernetes","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_version":"8.2112.0-2ubuntu2.5","binary_name":"rsyslog-mongodb"},{"binary_name":"rsyslog-mysql","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_name":"rsyslog-openssl","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_version":"8.2112.0-2ubuntu2.5","binary_name":"rsyslog-pgsql"},{"binary_name":"rsyslog-relp","binary_version":"8.2112.0-2ubuntu2.5"},{"binary_version":"8.2112.0-2ubuntu2.5","binary_name":"rsyslog-snmp"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-78002.json"}},{"package":{"name":"rsyslog","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/rsyslog?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.2312.0-3ubuntu9.4"}]}],"versions":["8.2306.0-2ubuntu2","8.2312.0-3ubuntu1","8.2312.0-3ubuntu2","8.2312.0-3ubuntu3","8.2312.0-3ubuntu7","8.2312.0-3ubuntu8","8.2312.0-3ubuntu9","8.2312.0-3ubuntu9.1","8.2312.0-3ubuntu9.2","8.2312.0-3ubuntu9.3"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_version":"8.2312.0-3ubuntu9.4","binary_name":"rsyslog"},{"binary_name":"rsyslog-czmq","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-elasticsearch","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-gnutls","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-gssapi","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_version":"8.2312.0-3ubuntu9.4","binary_name":"rsyslog-hiredis"},{"binary_name":"rsyslog-kafka","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-kubernetes","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_version":"8.2312.0-3ubuntu9.4","binary_name":"rsyslog-mongodb"},{"binary_name":"rsyslog-mysql","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-openssl","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-pgsql","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-relp","binary_version":"8.2312.0-3ubuntu9.4"},{"binary_name":"rsyslog-snmp","binary_version":"8.2312.0-3ubuntu9.4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-78002.json"}},{"package":{"name":"rsyslog","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/rsyslog?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.2512.0-1ubuntu4.2"}]}],"versions":["8.2504.0-1ubuntu2","8.2512.0-1ubuntu2","8.2512.0-1ubuntu3","8.2512.0-1ubuntu4","8.2512.0-1ubuntu4.1"],"ecosystem_specific":{"binaries":[{"binary_name":"rsyslog","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-clickhouse","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-czmq","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-docker","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_version":"8.2512.0-1ubuntu4.2","binary_name":"rsyslog-elasticsearch"},{"binary_name":"rsyslog-gnutls","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-gssapi","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-hiredis","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_version":"8.2512.0-1ubuntu4.2","binary_name":"rsyslog-kafka"},{"binary_name":"rsyslog-kubernetes","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-mongodb","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-mysql","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_version":"8.2512.0-1ubuntu4.2","binary_name":"rsyslog-openssl"},{"binary_name":"rsyslog-pgsql","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-relp","binary_version":"8.2512.0-1ubuntu4.2"},{"binary_name":"rsyslog-snmp","binary_version":"8.2512.0-1ubuntu4.2"}],"availability":"No 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