CVE-2021-33197 Missing authorization in n/a
Attackers can drop arbitrary headers in specific ReverseProxy configurations, potentially bypassing security controls in Go applications.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-33197?
CVE-2021-33197 is a medium-severity missing authorization 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
In Go before 1.15.13 and 1.16.x before 1.16.5, some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.
Weakness: CWE-862
Which versions are affected by CVE-2021-33197?
2 open source packages ship an affected version, including golang and stdlib. It affects 1 product.
| 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.
How do I fix CVE-2021-33197?
Upgrade golang to a fixed version for your release line: 1.15.13 or 1.16.5.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2021-33197 being exploited?
There is no known exploitation of CVE-2021-33197 in the wild and no public exploit code.
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- 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-79094, AZL-98925, BIT-golang-2021-33197, DEBIAN-CVE-2021-33197, GHSA-wqr7-cf9q-rvf7, GO-2021-0241 and 1 more.