Heap-based buffer overflow in rsyslog - CVE-2026-78002
Published: August 27, 2026
Vulnerability identifier: #VU146002
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-78002
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to heap-based buffer overflow in the RainerScript replace() and three-argument wrap() implementation when processing attacker-controlled message content from network input with an affected ruleset. A remote attacker can send a specially crafted message to cause a denial of service.
Exposure requires a configuration that applies replace() or three-argument wrap() to untrusted message data received from a network input.
Affected software
rsyslog
How to mitigate CVE-2026-78002
Install security update from vendor's repository.
rsyslog - update to 141