VULNERABILITY INTELLIGENCE
CVE-2026-72761
EPSS probability0.47%
CISA KEVNot currently listed
Published2026-08-10
Last modified2026-08-26
Description
The webhook URL validator in `website/notifications/webhooks.py` uses `ip.is_global` to reject non-public addresses after DNS resolution. IPv6 transition addresses (NAT64 `64:ff9b::/96`, 6to4 `2002::/16`, Teredo `2001:0000::/32`) are classified as globally routable by IANA, so `is_global` returns `True` even when the embedded IPv4 targets a private, loopback, or cloud metadata destination. An attacker can register a webhook pointing at a hostname that resolves to a transition address to bypass the SSRF guard and exfiltrate vulnerability data to an internal endpoint. The vulnerability was introduced on a non-release version. The fix was already done on HEAD. It only affects organisation running the HEAD.
Weakness classification
- 5a6e4751-2f3f-4070-9419-94fb35b644e8: CWE-918