CURL-CVE-2021-22876

    Dashboard / Vulnerabilities / CURL-CVE-2021-22876

    CURL-CVE-2021-22876

    Published: 31 Mar 2021Last Modified: 27 May 2026

    Summary: Automatic referer leaks credentials

    Details: libcurl does not strip off user credentials from the URL when automatically populating the `Referer:` HTTP request header field in outgoing HTTP requests, and therefore risks leaking sensitive data to the server that is the target of the second HTTP request. libcurl automatically sets the `Referer:` HTTP request header field in outgoing HTTP requests if the `CURLOPT_AUTOREFERER` option is set. With the curl tool, it is enabled with `--referer ";auto"`.

    References:

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: SEMVER

    Events:

    Introduced- 7.1.1
    Fixed -7.76.0

    Affected versions

    7.75.0

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CURL-CVE-2021-22876 | CVE-DB