{"id":"CVE-2024-45302","summary":"CRLF Injection in RestSharp's `RestRequest.AddHeader` method","details":"RestSharp is a Simple REST and HTTP API Client for .NET. The second argument to `RestRequest.AddHeader` (the header value) is vulnerable to CRLF injection. The same applies to `RestRequest.AddOrUpdateHeader` and `RestClient.AddDefaultHeader`. The way HTTP headers are added to a request is via the `HttpHeaders.TryAddWithoutValidation` method which does not check for CRLF characters in the header value. This means that any headers from a `RestSharp.RequestHeaders` object are added to the request in such a way that they are vulnerable to CRLF-injection. In general, CRLF-injection into a HTTP header (when using HTTP/1.1) means that one can inject additional HTTP headers or smuggle whole HTTP requests. If an application using the RestSharp library passes a user-controllable value through to a header, then that application becomes vulnerable to CRLF-injection. This is not necessarily a security issue for a command line application like the one above, but if such code were present in a web application then it becomes vulnerable to request splitting (as shown in the PoC) and thus Server Side Request Forgery. Strictly speaking this is a potential vulnerability in applications using RestSharp, not in RestSharp itself, but I would argue that at the very least there needs to be a warning about this behaviour in the RestSharp documentation. RestSharp has addressed this issue in version 112.0.0. All users are advised to upgrade. There are no known workarounds for this vulnerability.","aliases":["GHSA-4rr6-2v9v-wcpc"],"modified":"2026-08-12T03:51:12.099891114Z","published":"2024-08-29T21:18:43.261Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/45xxx/CVE-2024-45302.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-93"]},"references":[{"type":"WEB","url":"https://github.com/restsharp/RestSharp/blob/777bf194ec2d14271e7807cc704e73ec18fcaf7e/src/RestSharp/Request/HttpRequestMessageExtensions.cs#L32"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/45xxx/CVE-2024-45302.json"},{"type":"ADVISORY","url":"https://github.com/restsharp/RestSharp/security/advisories/GHSA-4rr6-2v9v-wcpc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-45302"},{"type":"FIX","url":"https://github.com/restsharp/RestSharp/commit/0fba5e727d241b1867bd71efc912594075c2934b"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/restsharp/restsharp","events":[{"introduced":"584fe59be8711c693a378fa7242d2d8e7b27ae52"},{"fixed":"0fba5e727d241b1867bd71efc912594075c2934b"}],"database_specific":{"extracted_events":[{"introduced":"107"},{"fixed":"112.0.0"},{"introduced":"107.0.0"}],"source":["AFFECTED_FIELD","CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:restsharp:restsharp:*:*:*:*:*:*:*:*"}}],"versions":["111.4.1","111.4.0","111.3.0","111.2.0","111.1.0","111.0.0","110.2.0","110.1.0","110.0.0","109.0.1","109.0.0","108.0.3","108.0.2","108.0.1","108.0.0","107.2.1","107.2.0","107.1.2","107.1.1","107.1.0","107.0.3","107.0.2","107.0.1","107.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-45302.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H"}]}