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.
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
| Link | Tags |
|---|---|
| https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txt | third party advisory patch |
| http://www.openwall.com/lists/oss-security/2021/07/25/1 | third party advisory mailing list |
| http://www.openwall.com/lists/oss-security/2021/08/03/1 | third party advisory mailing list |