Vulnerability · Published Sep 7, 2021 · Assigned by GitHub_M
CVE-2021-39194Denial of service while parsing polymorphic input with tagged polymorphism style in kaml
Medium 4.3
In plain English
A medium-severity infinite loop in kaml from charleskorn. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.7% (higher than 77% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
kaml is an open source implementation of the YAML format with support for kotlinx.serialization. In affected versions attackers that could provide arbitrary YAML input to an application that uses kaml could cause the application to endlessly loop while parsing the input. This could result in resource starvation and denial of service. This only affects applications that use polymorphic serialization with the default tagged polymorphism style. Applications using the property polymorphism style are not affected. YAML input for a polymorphic type that provided a tag but no value for the object would trigger the issue. Version 0.35.3 or later contain the fix for this issue.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | com.charleskorn.kaml:kaml | 0.35.3 | GHSA-fmm9-3gv8-58f4 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| charleskorn | kaml | < 0.35.2 |
Weakness: CWE-835 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
References
- https://github.com/charleskorn/kaml/security/advisories/GHSA-fmm9-3gv8-58f4 x_refsource_CONFIRM
- https://github.com/charleskorn/kaml/issues/179 x_refsource_MISC
- https://github.com/charleskorn/kaml/commit/e18785d043fc6324c81e968aae9764b4b060bc6a x_refsource_MISC