CVE-2026-67426 Flyto2 Core: Unauthenticated flyto-verification /run: callback_url SSRF and internal runner-secret exfiltration
Unauthenticated attackers can trigger SSRF and exfiltrate internal runner secrets via the verification service callback URL.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-67426?
CVE-2026-67426 is a critical server-side request forgery vulnerability in flytohub flyto-core, published on 29 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Flyto2 Core is an execution kernel for automation and AI-agent workflows. Prior to 2.26.7, the standalone flyto-verification service in src/core/verification_service.py exposes unauthenticated POST /run on 0.0.0.0:8344 and uses client-supplied callback_url for an outbound POST with X-Internal-Key: $FLYTO_RUNNER_SECRET while bypassing target_allowed, allowing unauthenticated SSRF and runner secret exfiltration. This issue is fixed in version 2.26.7.
Which versions are affected by CVE-2026-67426?
3 open source packages ship an affected version, including flyto-core.
| Package | Affected | Fixed in |
|---|---|---|
flyto-core PyPI | All versions | 2.26.7 |
flyto-core PyPI | From 2.26.6 | 2.26.7 |
flyto-core PyPI | From 2.26.6 | 2.26.7 |
How do I fix CVE-2026-67426?
Upgrade flyto-core to 2.26.7 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-67426 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-67426 exists.
Sources
Also known as GHSA-jx74-cqjv-2c67, PYSEC-2026-3571.