CVE-2026-71272 — HIGH (8.5)

Vulnerability Description

Memos' webhook dispatch function safeDialContext() (internal/webhook/webhook.go) resolves the target hostname via net.DefaultResolver.LookupHost() and validates the resulting IPs against reserved ranges, but then dials net.JoinHostPort(host, port) using the original hostname rather than the already-validated IP address. Because net.Dialer.DialContext() performs its own independent DNS resolution, an attacker controlling DNS for the webhook's hostname (e.g. via a short TTL) can return a public, allowed IP during validation and a different, internal IP at dial time — a classic time-of-check/time-of-use DNS-rebinding bypass of the SSRF protection.

CVSS Score

8.5

HIGH

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

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

CHANGED

Confidentiality

HIGH

Integrity

LOW

Availability

NONE

Related Weaknesses (CWE)

CWE-367

References

FAQ

What is CVE-2026-71272?

CVE-2026-71272 is a vulnerability with a CVSS score of 8.5 (HIGH). Memos' webhook dispatch function safeDialContext() (internal/webhook/webhook.go) resolves the target hostname via net.DefaultResolver.LookupHost() and validates the resulting IPs against reserved rang...

How severe is CVE-2026-71272?

CVE-2026-71272 has been rated HIGH with a CVSS base score of 8.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-71272?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.