CVE-2017-1000100 : What You Need to Know

A vulnerability in curl/libcurl could allow a malicious server to redirect a client to a crafted TFTP URL, potentially exposing sensitive memory contents.

Understanding CVE-2017-1000100

This CVE describes a security issue in the way curl/libcurl handles long file names during TFTP transfers.

What is CVE-2017-1000100?

When a TFTP transfer involves a URL with a file name longer than approximately 515 bytes, curl/libcurl truncates the file name to fit within buffer limits. However, the buffer size is incorrectly updated, leading to potential buffer overflow.

The Impact of CVE-2017-1000100

Exploiting this vulnerability could allow a malicious server to redirect a vulnerable client to a specially crafted TFTP URL, tricking it into sending sensitive memory contents to a remote server over UDP.

Technical Details of CVE-2017-1000100

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The issue arises from incorrect buffer size updates in curl/libcurl when handling long file names during TFTP transfers, potentially leading to buffer overflow.

Affected Systems and Versions

Product: n/a
Vendor: n/a
Versions: n/a

Exploitation Mechanism

By redirecting a client to a crafted TFTP URL, a malicious server can exploit the buffer overflow in curl/libcurl, leading to potential data leakage.

Mitigation and Prevention

Protecting systems from CVE-2017-1000100 requires immediate actions and long-term security practices.

Immediate Steps to Take

Limit curl's redirect protocols using the --proto-redir option
Set the CURLOPT_REDIR_PROTOCOLS option in libcurl to restrict redirect protocols

Long-Term Security Practices

Regularly update curl/libcurl to the latest versions
Implement network segmentation to limit exposure to potentially malicious servers

Patching and Updates

Apply relevant patches and updates provided by the respective vendors to address the vulnerability.