CVE-2020-28018

Exim 4 before 4.94.2 allows Use After Free in smtp_reset in certain situations that may be common for builds with OpenSSL.

• CWE-416

• http://www.openwall.com/lists/oss-security/2021/05/11/14Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/15Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/17Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/5Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/6Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/12/2Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/12/3Mailing List, Third Party Advisory
• https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28018-OCORK.txtVendor Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/14Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/15Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/17Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/5Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/11/6Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/12/2Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/12/3Mailing List, Third Party Advisory
• https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28018-OCORK.txtVendor Advisory

Published

May 6, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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