Fix Available for Use-After-Free Vulnerability in Tinyproxy

Summary

This is a vulnerability that exists in HTTP Connection Headers parsing in Tinyproxy 1.11.1 and Tinyproxy 1.10.1 classified as CVE-2024-49606 (CVSSv3: 9.8). Cisco Talos security researchers describe this vulnerability as a use-after-free which exists in the HTTP Connection Headers of vulnerable versions of tiny proxy. Utilizing a specially crafted HTTP header can trigger reuse of previously freed memory which leads to memory corruption and can potentially lead to remote code execution. This method does not require authentication. This vulnerability is considered a zero day, but a fix has been made available through GitHub.

Impact Assessment

This vulnerability is considered a zero day by Talos researchers and has the potential for a remote unauthenticated attacker to perform a remote code execution. This would have a high impact on confidentiality, integrity, and availability and should be patched swiftly.

Remediation

There is currently no official patch to tinyproxy, but the issue was fixed in a github commit to the master. Pulling this and manually applying it to your current instance of tinyproxy will remediate this vulnerability. The developer states an official fix will be available when version 1.11.2 of tinyproxy is released.

What It Means for You

If you or your organization utilizes tinyproxy navigate to the github commit and attempt to manually apply the change. This is a high severity zero day vulnerability and needs to be patched as soon as possible.

Business Implications

Exploitation of this vulnerability can allow an attacker to execute arbitrary code on an organization’s systems. This can result in the creation of a backdoor or installation of malware which will allow the attacker to take control of the affected devices and perform lateral movement. Monetary, data, and reputational loss can follow the exploitation as disaster recovery, incident response efforts, and business interruptions and inefficiencies will soon follow when this vulnerability is exploited.

Access Point Consulting Recommends

Patch: A fix is available on the master github for tinyproxy, it is recommended to pull this fix and manually apply it to the vulnerable tinyproxy instance.

Watch out for official patch: An official fix is coming to tinyproxy 1.11.2, it is advised to utilize that version when it is released.

Associated Bulletins

https://github.com/tinyproxy/tinyproxy/issues/533?ref=news.risky.biz

https://talosintelligence.com/vulnerability_reports/TALOS-2023-1889

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