CVE-2020-28020

Exim 4 before 4.92 allows Integer Overflow to Buffer Overflow, in which an unauthenticated remote attacker can execute arbitrary code by leveraging the mishandling of continuation lines during header-length restriction.

• CWE-190

• http://www.openwall.com/lists/oss-security/2021/07/25/1Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/08/03/1Mailing List, Third Party Advisory
• https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txtPatch, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/07/25/1Mailing List, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/08/03/1Mailing List, Third Party Advisory
• https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txtPatch, Third Party 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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