CVE-2026-61548 (GCVE-0-2026-61548)

Vulnerability from cvelistv5 – Published: 2026-09-18 16:54 – Updated: 2026-09-21 20:49
VLAI
Title
Rsyslog: mmpstrucdata stack buffer overflow with oversized RFC5424 structured data
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] 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.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-18 19:24 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7627 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rsyslog rsyslog Affected: >= 7.5.4, < 8.2606.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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