CVE-2021-33198 Denial of service in n/a
A remote attacker can cause a denial of service by providing a large exponent to the math/big.Rat SetString or UnmarshalText methods in the Go standard library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-33198?
CVE-2021-33198 is a high-severity denial of service 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, there can be a panic for a large exponent to the math/big.Rat SetString or UnmarshalText method.
Which versions are affected by CVE-2021-33198?
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-2021-33198?
Upgrade golang to a fixed version for your release line: 1.15.13 or 1.16.5.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-33198 being exploited?
There is no known exploitation of CVE-2021-33198 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 BIT-golang-2021-33198, DEBIAN-CVE-2021-33198, GHSA-q2pw-fq43-w78v, GO-2021-0242, UBUNTU-CVE-2021-33198.