CVE-2024-1135: Request Smuggling (CVSS 7.5)

Description

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Weakness Type (CWE)

CWE-444 CWE-444

References

Other References

https://huntr.com/bounties/22158e34-cfd5-41ad-97e0-a780773d96c1 https://lists.debian.org/debian-lts-announce/2024/06/msg00027.html https://huntr.com/bounties/22158e34-cfd5-41ad-97e0-a780773d96c1 https://lists.debian.org/debian-lts-announce/2024/06/msg00027.html https://lists.debian.org/debian-lts-announce/2024/12/msg00018.html

Frequently Asked Questions

What is CVE-2024-1135? +

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-1135? +

CVE-2024-1135 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

How do I check if I'm vulnerable to CVE-2024-1135? +

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-2024-1135