CVE-2026-78002
An unauthenticated remote attacker can trigger a heap buffer overflow in the RainerScript `replace()` function by sending specially crafted syslog messages.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.98%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.98% probability · 62th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-131
- Source
- secalert@redhat.com
EPSS 1.0% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://access.redhat.com/errata/RHSA-2026:69540
- https://access.redhat.com/errata/RHSA-2026:69541
- https://access.redhat.com/errata/RHSA-2026:71603
- https://access.redhat.com/errata/RHSA-2026:80817
- https://access.redhat.com/errata/RHSA-2026:81321
- https://access.redhat.com/errata/RHSA-2026:84576
- https://access.redhat.com/errata/RHSA-2026:86124
- https://access.redhat.com/errata/RHSA-2026:87408
- https://access.redhat.com/errata/RHSA-2026:90349
- https://access.redhat.com/security/cve/CVE-2026-78002
- https://bugzilla.redhat.com/show_bug.cgi?id=2521135
- https://github.com/rsyslog/rsyslog/security/advisories/GHSA-g72f-gc6v-f2w3
- http://www.openwall.com/lists/oss-security/2026/08/29/1
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.