CVE-2021-33195 Cross-site scripting in n/a
An attacker can inject malicious scripts via unsafe DNS replies in Go applications, potentially leading to cross-site scripting attacks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-33195?
CVE-2021-33195 is a high-severity cross-site scripting vulnerability in Golang Go, published on 2 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Go before 1.15.13 and 1.16.x before 1.16.5 has functions for DNS lookups that do not validate replies from DNS servers, and thus a return value may contain an unsafe injection (e.g., XSS) that does not conform to the RFC1035 format.
Weakness: CWE-74
Which versions are affected by CVE-2021-33195?
2 open source packages ship an affected version, including golang and stdlib. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
golang Bitnami | All versions | 1.15.13, 1.16.5 |
stdlib Go | All versions | 1.15.13, 1.16.5 |
Products include Golang Go, Netapp Cloud Insights Telegraf Agent.
How do I fix CVE-2021-33195?
Upgrade golang to a fixed version for your release line: 1.15.13 or 1.16.5.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2021-33195 being exploited?
There is no known exploitation of CVE-2021-33195 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-78998, AZL-98889, BIT-golang-2021-33195, DEBIAN-CVE-2021-33195, GHSA-xf7m-5vgf-jhv9, GO-2021-0239 and 1 more.