CVE-2017-15042 Information disclosure in n/a
Go's SMTP client may send credentials in cleartext if a malicious server disables TLS, exposing usernames and passwords to attackers.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2017-15042?
CVE-2017-15042 is a medium-severity vulnerability in Golang Go, published on 5 Oct 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-319
Which versions are affected by CVE-2017-15042?
1 open source package ship an affected version, including stdlib. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
stdlib Go | From 1.1.0-0 | 1.8.4, 1.9.1 |
Products include Golang Go.
How do I fix CVE-2017-15042?
Upgrade stdlib to a fixed version for your release line: 1.8.4 or 1.9.1.
Is CVE-2017-15042 being exploited?
There is no known exploitation of CVE-2017-15042 in the wild and no public exploit code.
Other vulnerabilities in Golang Go
- CVE-2020-0601 Microsoft Windows CryptoAPI Spoofing
- CVE-2026-27143 Missing bound checks can lead to memory corruption in safe Go in cmd/compile
- CVE-2024-24790 Unexpected behavior from Is methods for IPv4-mapped IPv6 addresses in net/netip
- CVE-2023-39320 Arbitrary code execution via go.mod toolchain directive in cmd/go
- CVE-2023-24540 Improper handling of JavaScript whitespace in html/template
Sources
Also known as AZL-79072, AZL-98781, GHSA-crv5-fmcw-6rw4, GO-2021-0178, UBUNTU-CVE-2017-15042.