Description
Memos' webhook URL validation, isReservedIP (internal/webhook/validate.go), checks a candidate IP against a reservedCIDRs list that omits 0.0.0.0/8 and never calls ip.IsUnspecified — unlike the correctly implemented sibling function isInternalIP in internal/httpgetter/html_meta.go, which does.
References2
Metrics
- CVSS 3.1
-
8.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N - EPSS — exploit probability
- 0% percentile: 26 · as of 13 November 2026
- CWE
- CWE-918
Could this be exploited in your environment?
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