cvedb.io
CVE-2021-3618
HIGH · CVSS 7.4
EPSS exploitation probability: 0%
Published 2022-03-23T20:15:09.833 · Last modified 2026-06-17T04:05:27.083

Summary

ALPACA is an application layer protocol content confusion attack, exploiting TLS servers implementing different protocols but using compatible certificates, such as multi-domain or wildcard certificates. A MiTM attacker having access to victim's traffic at the TCP/IP layer can redirect traffic from one subdomain to another, resulting in a valid TLS session. This breaks the authentication of TLS and cross-protocol attacks may be possible where the behavior of one protocol service may compromise the other at the application layer.

Affected products

f5 — nginx

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.