CVE-2026-18581
Description
A flaw was found in llama.cpp. A local attacker can exploit this vulnerability by manipulating input to the Jinja Minja Template Parser component. This manipulation can lead to a reachable assertion, causing the application to terminate unexpectedly. This results in a Denial of Service (DoS).
Statement
This flaw has a Moderate impact. The Jinja/Minja chat-template parser in llama.cpp (common/jinja/parser.cpp) does not validate the syntactic correctness of template input; a local user who supplies a malformed template such as {{9|9|{ triggers a reachable assertion that aborts the process, resulting in a denial of service. Exploitation requires local access and the ability to submit a chat template to the parser, and the impact is limited to availability of the affected process. No Red Hat enterprise product ships llama.cpp; only the Fedora community packages llama-cpp and python-llama-cpp-python are affected, for which community trackers have been filed for maintainer action.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Understanding the Weakness (CWE)
Other
Technical Impact: Varies by Context
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