CURL-CVE-2017-1000100

    Dashboard / Vulnerabilities / CURL-CVE-2017-1000100

    CURL-CVE-2017-1000100

    Published: 9 Aug 2017Last Modified: 27 May 2026

    Summary: TFTP sends more than buffer size

    Details: When doing a TFTP transfer and curl/libcurl is given a URL that contains a long filename (longer than about 515 bytes), the filename is truncated to fit within the buffer boundaries, but the buffer size is still wrongly updated to use the original length. This too large value is then used in the `sendto()` call, making curl attempt to send more data than what is actually put into the buffer. The `sendto()` function then reads beyond the end of the heap based buffer. A malicious HTTP(S) server could redirect a vulnerable libcurl-using client to a crafted TFTP URL (if the client has not restricted which protocols it allows redirects to) and trick it to send private memory contents to a remote server over UDP. Limit curl's redirect protocols with `--proto-redir` and libcurl's with `CURLOPT_REDIR_PROTOCOLS`.

    References:

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: SEMVER

    Events:

    Introduced- 7.15.0
    Fixed -7.55.0

    Affected versions

    7.54.1
    7.54.0

    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