libESMTP through 1.0.6 mishandles domain copying into a fixed-size buffer in ntlm_build_type_2 in ntlm/ntlmstruct.c, as demonstrated by a stack-based buffer over-read.

References

• https://nvd.nist.gov/vuln/detail/CVE-2019-19977
• https://github.com/Kirin-say/Vulnerabilities/blob/master/Stack_Overflow_in_libesmtp.md
• https://github.com/jbouse-debian/libesmtp/blob/ca5bd0800ef1da234315da4c59716568eb5e6402/ntlm/ntlmstruct.c#L228-L242
• https://web.archive.org/web/20190528215510/http://brianstafford.info/libesmtp/