CVE-2026-108602: Helicone through v2025.08.21-1 SSRF via Jawn Webhook Sender DNS Resolution

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-10 · updated 2026-10-18
Weakness: CWE-918

Description

Helicone through v2025.08.21-1 contains a server-side request forgery vulnerability in the Jawn webhook sender that allows authenticated organization users to reach internal services by using hostnames resolving to private addresses. Attackers can create webhooks with public hostnames that resolve or DNS-rebind to loopback or internal addresses, causing blind POST requests to internal HTTPS services.

Affected products

helicone: through v2025.08.21-1

References

https://github.com/Helicone/helicone
https://github.com/Helicone/helicone/blob/067d9290acb4f1fc9320e902fc67b4b399b50363/valhalla/jawn/src/controllers/public/webhookController.ts#L64-L85
https://github.com/Helicone/helicone/blob/067d9290acb4f1fc9320e902fc67b4b399b50363/valhalla/jawn/src/lib/clients/webhookSender.ts#L11-L76
https://hackmd.io/@haind/helicone-webhook-dns-ssrf
https://www.vulncheck.com/advisories/helicone-through-2025.08.21-1-ssrf-via-jawn-webhook-sender-dns-resolution

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