High
Rsyslog: rsyslog: denial of service via heap buffer overflow in rainerscript replace() function
Type: advisorySources: Official CVE List
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.
- Products
- Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 8.8 Telecommunications Update Service, Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.6 Extended Update Support, Red Hat Update Infrastructure 5
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-78002
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 13:04 UTC · Revision 2
Source evidence
Rsyslog: rsyslog: denial of service via heap buffer overflow in rainerscript replace() function
core-cve · Original sourcePublished 27 Aug 2026, 16:12 UTC
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.
cve:CVE-2026-78002
Red Hat Enterprise Linux 10
Fixed versions: Not specified
Red Hat Enterprise Linux 10.0 Extended Update Support
Fixed versions: Not specified
Red Hat Enterprise Linux 8
Fixed versions: Not specified
Red Hat Enterprise Linux 8.8 Telecommunications Update Service
Fixed versions: Not specified
Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
Fixed versions: Not specified
Red Hat Enterprise Linux 9
Fixed versions: Not specified
Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions
Fixed versions: Not specified
Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions
Fixed versions: Not specified
Red Hat Enterprise Linux 9.6 Extended Update Support
Fixed versions: Not specified
Red Hat Update Infrastructure 5
Fixed versions: Not specified
Red Hat Enterprise Linux 6
Fixed versions: Not specified
Red Hat Enterprise Linux 6
Fixed versions: Not specified
Red Hat Enterprise Linux 7
Fixed versions: Not specified
Complete source record
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