CVE-2026-17501 ggml-org llama.cpp JSON-Schema-to-GBNF Conversion json-schema-to-grammar.cpp transform recursion
Remote attackers can cause denial of service via uncontrolled recursion in the JSON-Schema-to-GBNF conversion function of the llama.cpp library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-17501?
CVE-2026-17501 is a medium-severity denial of service vulnerability in ggml-org llama.cpp, published on 27 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A flaw has been found in ggml-org llama.cpp e15efe0. This vulnerability affects the function transform of the file common/json-schema-to-grammar.cpp of the component JSON-Schema-to-GBNF Conversion. This manipulation causes uncontrolled recursion. The attack may be initiated remotely. The pull request to fix this issue awaits acceptance.
Which versions are affected by CVE-2026-17501?
How do I fix CVE-2026-17501?
No fix has been published for CVE-2026-17501 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-17501 being exploited?
There is no known exploitation of CVE-2026-17501 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-17501, GHSA-h334-888w-8prr, UBUNTU-CVE-2026-17501.