Description
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.
References10
- access.redhat.com/errata/RHSA-2026:69540
- access.redhat.com/errata/RHSA-2026:69541
- access.redhat.com/errata/RHSA-2026:71603
- access.redhat.com/errata/RHSA-2026:80817
- access.redhat.com/errata/RHSA-2026:81321
- access.redhat.com/errata/RHSA-2026:84576
- access.redhat.com/errata/RHSA-2026:86124
- access.redhat.com/errata/RHSA-2026:87408
- access.redhat.com/errata/RHSA-2026:90349
- access.redhat.com/errata/RHSA-2026:91582
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 65 · as of 9 November 2026
- CWE
- CWE-131
Could this be exploited in your environment?
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