Threat Intelligence Database

A vulnerability in the h11 HTTP library used by Uvicorn allows acceptance of malformed HTTP/1.1 chunked-encoding bodies due to lenient parsing of trailing bytes. This can cause request smuggling when combined with a proxy that parses chunked bodies differently. The issue is fixed in h11 version 0.15.0. Exploitation requires both a buggy h11 and a buggy proxy, so fixing either component mitigates the risk.

A vulnerability in the idna.encode() function of the kimi-cli package allows specially crafted inputs to bypass the previous fix for CVE-2024-3651, causing excessive resource consumption and potential denial-of-service. The issue arises from insufficient early rejection of overly long inputs, leading to expensive processing. Versions prior to 3.14 do not implement the improved input length checks. The vulnerability has a medium severity with a CVSS score of 5.3. Official patches are available starting from version 3.14, which implement early input length rejection to mitigate the issue.

This is the same issue as CVE-2024-3651, however the original remediation in 2024 was not a complete fix. Payloads such as `"\u0660" * N` or `"\u30fb" * N + "\u6f22"` utilize the `valid_contexto` function prior to length rejection, and for high values of `N` will take a long time to process. ### Impact A specially crafted argument to the `idna.encode()` function could consume significant resources. This may lead to a denial-of-service. ### Patches Starting in version 3.14, the function rejects long inputs as soon as practicable prior to any further processing to minimize resource consumption. In version 3.15, this approach was extended to lesser used alternate functions (i.e. per-label conversions and codec support). ### Workarounds Domain names cannot exceed 253 characters in length, if this length limit is enforced prior to passing the domain to the `idna.encode()` function it should no longer consume significant resources. This is triggered by arbitrarily large inputs that would not occur in normal usage, but may be passed to the library assuming there is no preliminary input validation by the higher-level application.

### Impact A specially crafted argument to the `idna.encode()` function could consume significant resources. This may lead to a denial-of-service. ### Patches The function has been refined to reject such strings without the associated resource consumption in version 3.7. ### Workarounds Domain names cannot exceed 253 characters in length, if this length limit is enforced prior to passing the domain to the `idna.encode()` function it should no longer consume significant resources. This is triggered by arbitrarily large inputs that would not occur in normal usage, but may be passed to the library assuming there is no preliminary input validation by the higher-level application. ### References * https://huntr.com/bounties/93d78d07-d791-4b39-a845-cbfabc44aadb