CVE-2023-46218

Published Dec 7, 2023

Last updated a year ago

CVSS medium 6.5
Curl
Libcurl

Overview

Description
This flaw allows a malicious HTTP server to set "super cookies" in curl that are then passed back to more origins than what is otherwise allowed or possible. This allows a site to set cookies that then would get sent to different and unrelated sites and domains. It could do this by exploiting a mixed case flaw in curl's function that verifies a given cookie domain against the Public Suffix List (PSL). For example a cookie could be set with `domain=co.UK` when the URL used a lower case hostname `curl.co.uk`, even though `co.uk` is listed as a PSL domain.
Source
support@hackerone.com
NVD status
Modified

Risk scores

CVSS 3.1

Type
Primary
Base score
6.5
Impact score
2.5
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

Configurations

Related CVEs

  1. ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to 7.1.2-16 and 6.9.13-41, an overflow on 32-bit systems can cause a crash in the SFW decoder when processing extremely large images. This vulnerability is fixed in 7.1.2-16 and 6.9.13-41.•CVE-2026-31853
  2. When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer performs a redirect to a second URL, curl could leak that token to the second hostname under some circumstances. If the hostname that the first request is redirected to has information in the used .netrc file, with either of the `machine` or `default` keywords, curl would pass on the bearer token set for the first host also to the second one.•CVE-2026-3783
  3. curl would wrongly reuse an existing HTTP proxy connection doing CONNECT to a server, even if the new request uses different credentials for the HTTP proxy. The proper behavior is to create or use a separate connection.•CVE-2026-3784
  4. When doing a second SMB request to the same host again, curl would wrongly use a data pointer pointing into already freed memory.•CVE-2026-3805
  5. libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When reusing a connection a range of criterion must first be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different credentials. One underlying reason being that Negotiate sometimes authenticates *connections* and not *requests*, contrary to how HTTP is designed to work. An application that allows Negotiate authentication to a server (that responds wanting Negotiate) with `user1:password1` and then does another operation to the same server also using Negotiate but with `user2:password2` (while the previous connection is still alive) - the second request wrongly reused the same connection and since it then sees that the Negotiate negotiation is already made, it just sends the request over that connection thinking it uses the user2 credentials when it is in fact still using the connection authenticated for user1... The set of authentication methods to use is set with `CURLOPT_HTTPAUTH`. Applications can disable libcurl's reuse of connections and thus mitigate this problem, by using one of the following libcurl options to alter how connections are or are not reused: `CURLOPT_FRESH_CONNECT`, `CURLOPT_MAXCONNECTS` and `CURLMOPT_MAX_HOST_CONNECTIONS` (if using the curl_multi API).•CVE-2026-1965

References

Sources include official advisories and independent security research.