CVE-2026-78002

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 17:20

Updated : 2026-09-04 09:17

NVD link : CVE-2026-78002

Mitre link : CVE-2026-78002

CVE.ORG link : CVE-2026-78002

JSON object : View

Products Affected

No product.

CWE

CWE-131

Incorrect Calculation of Buffer Size

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