An unintended cleartext issue exists in Go before 1.8.4 and 1.9.x before 1.9.1. RFC 4954 requires that, during SMTP, the PLAIN auth scheme must only be used on network connections secured with TLS. The original implementation of smtp.PlainAuth in Go 1.0 enforced this requirement, and it was documented to do so. In 2013, upstream issue #5184, this was changed so that the server may decide whether PLAIN is acceptable. The result is that if you set up a man-in-the-middle SMTP server that doesn't advertise STARTTLS and does advertise that PLAIN auth is OK, the smtp.PlainAuth implementation sends the username and password.
CVSS Details
- CVSS 3.0 Base Score: 5.9
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade go | Oct 25, 2017 | Oct 5, 2017 |
| Amazon Linux Ami 2 | — | Upgrade golang-miscUpgrade golang-testsUpgrade golang-binUpgrade golang-srcUpgrade golangUpgrade golang-docs | Apr 27, 2020 | Oct 5, 2017 |
| Amazon_linux | — | Upgrade golang | Nov 3, 2017 | Oct 5, 2017 |
| Centos_linux | — | Upgrade golang-binUpgrade golang-docsUpgrade golang-testsUpgrade golang-srcUpgrade golangUpgrade golang-misc | Aug 28, 2019 | Oct 5, 2017 |
| Gentoo Linux | — | Upgrade dev-lang/go. | Oct 30, 2017 | Oct 5, 2017 |
| Oracle Solaris | — | Upgrade system/library/gcc/gcc-go-runtime-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-c-runtime to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-c-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-gobjc-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-gobjc-runtime-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-gfortran-runtime-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-go-runtime to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-gfortran to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-gobjc-runtime to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-c-runtime-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-gfortran-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-c++ to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-go-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-runtime to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-common-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-runtime-9 to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-gobjc to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade system/library/gcc/gcc-gfortran-runtime to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4Upgrade developer/gcc/gcc-go to version 9.2.0-11.4.21.0.1.69.0 on Solaris 11.4 | Jan 19, 2021 | Oct 5, 2017 |
| Redhat_linux | — | Upgrade golang-binUpgrade golang-docsUpgrade golang-testsUpgrade golangUpgrade golang-miscUpgrade golang-src | Apr 11, 2018 | Oct 5, 2017 |
| Suse | — | Upgrade go | Aug 9, 2024 | Oct 5, 2017 |
| Ubuntu | — | No solution exists | Jun 26, 2025 | Oct 5, 2017 |
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