CVE-2022-36055: Denial of service in Helm
Fuzz testing, by Ada Logics and sponsored by the CNCF, identified input to functions in the strvals package that can cause an out of memory panic. Out of memory panics cannot be recovered from. Applications that use functions from the strvals package in the Helm SDK can have a Denial of Service attack when they use this package and it panics.
Impact
The strvals package contains a parser that turns strings into Go structures. For example, the Helm client has command line flags like --set, --set-string, and others that enable the user to pass in strings that are merged into the values. The strvals package converts these strings into structures Go can work with. Some string inputs can cause array data structures to be created causing an out of memory panic.
Applications that use the strvals package in the Helm SDK to parse user supplied input can suffer a Denial of Service when that input causes a panic that cannot be recovered from.
The Helm Client will panic with input to --set, --set-string, and other value setting flags that causes an out of memory panic. Helm is not a long running service so the panic will not affect future uses of the Helm client.
Patches
This issue has been resolved in 3.9.4.
Workarounds
SDK users can validate strings supplied by users won't create large arrays causing significant memory usage before passing them to the strvals functions.
For more information
Helm's security policy is spelled out in detail in our SECURITY document.
Credits
Disclosed by Ada Logics in a fuzzing audit sponsored by CNCF.
Other sources
Helm is a tool for managing Charts. Charts are packages of pre-configured Kubernetes resources. Fuzz testing, provided by the CNCF, identified input to functions in the strvals package that can cause an out of memory panic. The strvals package contains a parser that turns strings in to Go structures. The strvals package converts these strings into structures Go can work with. Some string inputs can cause array data structures to be created causing an out of memory panic. Applications that use the strvals package in the Helm SDK to parse user supplied input can suffer a Denial of Service when that input causes a panic that cannot be recovered from. The Helm Client will panic with input to --set, --set-string, and other value setting flags that causes an out of memory panic. Helm is not a long running service so the panic will not affect future uses of the Helm client. This issue has been resolved in 3.9.4. SDK users can validate strings supplied by users won't create large arrays causing significant memory usage before passing them to the strvals functions.
Helm is vulnerable to a denial of service, caused by a flaw in the strvals package. By sending a specially-crafted input, a remote attacker could exploit this vulnerability to cause memory panics, and results in a denial of service condition.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2022-36055?
CVE-2022-36055 is a vulnerability in Helm that can lead to a denial of service due to a flaw in the strvals package.
What is the severity of CVE-2022-36055?
CVE-2022-36055 has a severity rating of 7.5 (high).
Which software is affected by CVE-2022-36055?
Helm versions between 3.0.0 and 3.9.4 are affected by CVE-2022-36055.
How can I fix CVE-2022-36055?
To fix CVE-2022-36055, you should update your Helm installation to version 3.9.4.
Where can I find more information about CVE-2022-36055?
For more information about CVE-2022-36055, you can refer to the following links: [GitHub Releases](https://github.com/helm/helm/releases/tag/v3.9.4), [GitHub Security Advisories](https://github.com/helm/helm/security/advisories/GHSA-7hfp-qfw3-5jxh), [NVD](https://nvd.nist.gov/vuln/detail/CVE-2022-36055).