{"id":"CVE-2026-61548","title":"Rsyslog is a rocket-fast system for log processing","summary":"Rsyslog is a rocket-fast system for log processing. From 7.5.4 until 8.2606.0, the optional mmpstrucdata plugin's parseSD_PARAM function in plugins/mmpstrucdata/mmpstrucdata.c stores RFC5424 parameter values in a fixed pVal[32 * 1024] st…","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-121","CWE-120"],"vendor":"rsyslog","product":"rsyslog","affected":["rsyslog >= 7.5.4, < 8.2606.0"],"published":"2026-09-18","updated":"2026-09-24","sourceUpdated":"2026-09-24T21:22:19.873","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-61548","references":[{"url":"https://github.com/rsyslog/rsyslog/commit/bcda60a3692efdf0c8e44102528f5a0ebe0dec6d","label":"security-advisories@github.com"},{"url":"https://github.com/rsyslog/rsyslog/pull/6991","label":"security-advisories@github.com"},{"url":"https://github.com/rsyslog/rsyslog/releases/tag/v8.2606.0","label":"security-advisories@github.com"},{"url":"https://github.com/rsyslog/rsyslog/security/advisories/GHSA-8qmr-c66f-g368","label":"security-advisories@github.com"},{"url":"http://www.openwall.com/lists/oss-security/2026/07/20/1","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-61548.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-61548"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2538148"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-61548"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-61548"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.0094,"epssPercentile":0.60747,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-09-18T19:24:39.206415Z"},"ingestedAt":"2026-09-18T17:46:41.520Z","scores":{"nvd":8.1,"vendor":7.5},"slug":"CVE-2026-61548","body":"## Overview\n\nRsyslog is a rocket-fast system for log processing. From 7.5.4 until 8.2606.0, the optional mmpstrucdata plugin's parseSD_PARAM function in plugins/mmpstrucdata/mmpstrucdata.c stores RFC5424 parameter values in a fixed pVal[32 * 1024] stack buffer and calls parsePARAM_VALUE without supplying the destination size. A remote unauthenticated attacker whose crafted RFC5424 message reaches an action using mmpstrucdata can provide a structured-data parameter larger than that buffer when MaxMessageSize permits it, causing an attacker-controlled stack overwrite. Deployments that do not install and use the plugin, or whose effective message-size limit remains below the required threshold, are not affected by this issue. The demonstrated impact is a crash and interruption of log collection; code execution is not demonstrated. This issue is fixed in version 8.2606.0.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · updated 2026-09-25 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-61548.json)","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}