CVE-2026-16651 temporalio/sqlparser malformed MySQL version comments can cause a panic
An authenticated attacker can cause a denial of service in Temporal Server by submitting malformed SQL queries that trigger a parser panic.
- 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-2026-16651?
CVE-2026-16651 is a high-severity denial of service vulnerability in Temporal Server, published on 21 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
temporalio/sqlparser can panic when Parse, ParseStrictDDL, or ParseNext processes a MySQL version comment whose contents are empty or consist only of one to five decimal digits. ExtractMysqlComment does not check the -1 result returned by strings.IndexFunc before using it as a slice boundary. The resulting Go runtime panic propagates unless the caller recovers it on the parsing goroutine, so applications that parse attacker-controlled SQL can terminate. Temporal Server exposes the affected parser through ListWorkers. When that API is enabled, an authenticated caller with namespace read permission can submit a malformed query that terminates the receiving Matching process. Repeated requests can sustain a denial of service. The issue affects availability only; no confidentiality or integrity impact was identified.
Weakness: CWE-129
Which versions are affected by CVE-2026-16651?
How do I fix CVE-2026-16651?
No fix has been published for CVE-2026-16651 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-2026-16651 being exploited?
There is no known exploitation of CVE-2026-16651 in the wild and no public exploit code.
Sources
Also known as GHSA-g9jq-gq4v-4rw3.