CVE-2024-39920 (CVSS 4.3)

Description

The TCP protocol in RFC 9293 has a timing side channel that makes it easier for remote attackers to infer the content of one TCP connection from a client system (to any server), when that client system is concurrently obtaining TCP data at a slow rate from an attacker-controlled server, aka the "SnailLoad" issue. For example, the attack can begin by measuring RTTs via the TCP segments whose role is to provide an ACK control bit and an Acknowledgment Number.

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CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Weakness Type (CWE)

CWE-1255 CWE-1255

References

Other References

https://github.com/IAIK/SnailLoad https://news.ycombinator.com/item?id=40809629 https://twitter.com/tugraz/status/1805272833322299412 https://www.instagram.com/p/C8wpO1UtExw/ https://www.rfc-editor.org/rfc/rfc9293.txt https://www.snailload.com https://www.snailload.com/snailload.pdf https://www.tugraz.at/en/tu-graz/services/news-stories/tu-graz-news/singleview/article/neue-sicherheitsluecke-erlaubt-ueberwachung-besuchter-websites-und-angesehener-videos https://github.com/IAIK/SnailLoad https://news.ycombinator.com/item?id=40809629

Frequently Asked Questions

What is CVE-2024-39920? +

The TCP protocol in RFC 9293 has a timing side channel that makes it easier for remote attackers to infer the content of one TCP connection from a client system (to any server), when that client system is concurrently obtaining TCP data at a slow rate from an attacker-controlled server, aka the "SnailLoad" issue. For example, the attack can begin by measuring RTTs via the TCP segments whose role is to provide an ACK control bit and an Acknowledgment Number. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2024-39920? +

CVE-2024-39920 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2024-39920? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2024-39920