Denial of service in string value parsing in helm.sh/helm/v3
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 an error that cannot be recovered from. 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 can cause a stack overflow to be created causing a stack overflow error. Stack overflow errors cannot be recovered from. The Helm Client will panic with input to --set, --set-string, and other value setting flags that causes a stack overflow. Helm is not a long running service so the error will not affect future uses of the Helm client.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
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 an error that cannot be recovered from. 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 can cause a stack overflow to be created causing a stack overflow error. Stack overflow errors cannot be recovered from. The Helm Client will panic with input to --set, --set-string, and other value setting flags that causes a stack overflow. Helm is not a long running service so the error will not affect future uses of the Helm client.
Fuzz testing, by Ada Logics and sponsored by the CNCF, identified input to functions in the _strvals_ package that can cause a stack overflow. In Go, a stack overflow 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 a stack overflow. 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 a stack overflow. 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 3.10.3. ### 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](https://github.com/helm/community/blob/master/SECURITY.md) document. ### Credits Disclosed by Ada Logics in a fuzzing audit sponsored by CNCF.
Helm is a tool for managing Charts, pre-configured Kubernetes resources. Versions prior to 3.10.3 are subject to Uncontrolled Resource Consumption, resulting in Denial of Service. Input to functions in the _strvals_ package can cause a stack overflow. In Go, a stack overflow 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. This issue has been patched in 3.10.3. 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 a tool for managing Charts, pre-configured Kubernetes resources. Versions prior to 3.10.3 are subject to Uncontrolled Resource Consumption, resulting in Denial of Service. Input to functions in the _strvals_ package can cause a stack overflow. In Go, a stack overflow 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. This issue has been patched in 3.10.3. SDK users can validate strings supplied by users won't create large arrays causing significant memory usage before passing them to the _strvals_ functions.
05 / REFERENCES
Further evidence
- https://github.com/helm/helm/commit/3636f6824757ff734cb265b8770efe48c1fb3737
- https://github.com/helm/helm/security/advisories/GHSA-6rx9-889q-vv2r
- https://github.com/helm/helm
- https://nvd.nist.gov/vuln/detail/CVE-2022-23524
- https://pkg.go.dev/vuln/GO-2022-1167
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/23xxx/CVE-2022-23524.json