CVE-2026-108602

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.

CVSS 4.0

5.3CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

4.3CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

EPSS

0.2% chance of exploitation in the next 30 days; higher than 11% of CVEs (scores of 2026-10-25)

CWE

CWE-918

Published

2026-10-10

Modified

2026-10-18

Record from

the NVD, synced 2026-10-19

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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