CVE-2026-18581Public exploit

Service abort via unchecked Jinja filter operand

Published Aug 3, 2026 · Updated Aug 3, 2026

Reachable assertion in llama.cpp e15efe0 allows local users to abort a server by supplying a malformed Jinja chat template. The parser accepts a literal after the pipe operator without validating its operand type, so the runtime chk_type assertion calls abort(). Exploitation requires access to submit a user-controlled chat_template; the result is an availability-only server process termination.

CVSS severity3.3
Low
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Reachable assertion in llama.cpp e15efe0 allows local users to abort a server by supplying a malformed Jinja chat template. The parser accepts a literal after the pipe operator without validating its operand type, so the runtime chk_type assertion calls abort(). Exploitation requires access to submit a user-controlled chat_template; the result is an availability-only server process termination.

The record

CVE
CVE-2026-18581
Published
Aug 3, 2026
Updated
Aug 3, 2026
Vendor
Georgi Gerganov
Product
llama.cpp
Classifications
CWE-617, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=e15efe0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Georgi Gerganov · llama.cppversion=e15efe0

Published CVSS scores

1.9VulDBCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
1.7VulDBAV:L/AC:L/Au:S/C:N/I:N/A:P
3.3VulDBCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-617Reachable Assertion
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo