Vulnerability in Ericlbuehler Mistral.rs
CVE-2026-124028
mistral.rs before 0.9.5 contains a delimiter injection vulnerability in mistralrs-core that allows attackers to inject tool calls by placing delimiter strings in text the model quotes. Attackers controlling documents, web pages or tool outputs can embed tags like </tool_call> to make qwen-xml, gemma4 or reasoning parsers return extra calls to declared tools with attacker-chosen arguments.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/EricLBuehler/mistral.rs (product)
- Patch Commit (patch)
- github.com/EricLBuehler/mistral.rs/pull/2455 (issue-tracking, patch)
- mistral.rs v0.9.5 Release Notes (release-notes)
- GitHub Security Advisory (GHSA-34w8-j94f-8c5w) (vendor-advisory)
- VulnCheck Advisory: mistral.rs before 0.9.5 Tool Call Injection via mistralrs-core Output Parsers (third-party-advisory)
Frequently asked questions
- What is CVE-2026-124028?
- CVE-2026-124028 is a medium-severity vulnerability in Ericlbuehler Mistral.rs, classified under CWE-140. CVSS score: 4.2/10. Published 2026-11-06.
- How severe is CVE-2026-124028?
- Medium severity. CVSS v3 base score is 4.2 out of 10.