Bug 2502868 (CVE-2026-19654)

Summary: CVE-2026-19654 rsyslog: A configuration-dependent issue in rsyslog's optional imptcp input module can allow an unauthenticated remote peer to crash rsyslogd
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: rhel-process-autobot, security-response-team, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: ---
Doc Text:
A unauthenticated remote peer may lead rsyslogd to crash due to a flaw in the optional imptcp module. A crafted input sequence during oversize-frame recovery can cause an invalid internal message length and terminate rsyslogd. No confidentiality or integrity impact, privilege escalation, or code execution has been identified. imtcp and the default imptcp framing modes are not affected.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2513565    
Bug Blocks:    
Deadline: 2026-07-22   

Description OSIDB Bzimport 2026-07-20 16:58:53 UTC 
A configuration-dependent issue in rsyslog's optional imptcp input module can allow an unauthenticated remote peer to crash rsyslogd. The issue is not active in a default installation. Exploitation requires all of the following:

* imptcp is explicitly loaded.
* An imptcp listener uses the non-default framing.delimiter.regex mode.
* An attacker can establish a TCP connection to that listener.

A crafted input sequence during oversize-frame recovery can cause an invalid internal message length and terminate rsyslogd. No confidentiality or integrity impact, privilege escalation, or code execution has been identified. imtcp and the default imptcp framing modes are not affected.