{"id":"AZL-9220","summary":"CVE-2021-3618 affecting package sendmail 8.15.2-46","details":"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.","modified":"2026-04-01T05:23:30.802573Z","published":"2022-03-23T20:15:09Z","upstream":["CVE-2021-3618"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-3618"}],"affected":[{"package":{"name":"sendmail","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/sendmail"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"8.15.2-46"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-9220.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"}]}