HashiCorp Vault has Server-Side Request Forgery in ACME Challenge Validation via Attacker-Controlled DNS
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Affected versions
1.14.0 and later (no fix listed)
Details
Vault’s PKI engine’s ACME validation did not reject local targets when issuing http-01 and tls-alpn-01 challenges. This may lead to these requests being sent to local network targets, potentially leading to information disclosure. Fixed in Vault Community Edition 2.0.0 and Vault Enterprise 2.0.0, 1.21.5, 1.20.10, and 1.19.16.
The fix
No fix commit could be resolved for this advisory (it may reference an issue tracker or a non-GitHub patch). See the references below.