CVE-2021-40346

An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, allowing an attacker to bypass all configured http-request HAProxy ACLs and possibly other ACLs.

CVSS v3.1

7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS v2.0

5.0 MEDIUMAV:N/AC:L/Au:N/C:N/I:P/A:N

EPSS

57.93% chance of exploitation in the next 30 days, 99th percentile

Published

2021-09-08

Updated

2024-08-04

Proof-of-concept exploits (7)

• Vulnmachines/HAProxy_CVE-2021-403465★ · 2022-09-20
• alexOarga/CVE-2021-403460★ · 2022-01-24
• alikarimi999/CVE-2021-403465★ · 2021-09-13
• donky16/CVE-2021-40346-POC32★ · 2021-09-28
• knqyf263/CVE-2021-4034641★ · 2021-09-08
• rizemon/CS53312★ · 2023-04-25
• jmg0929/CVE-2021-40346

References

• CVE Record
• NVD entry

Related

• CVE-2021-21315
• CVE-2015-5477
• CVE-2018-1111
• CVE-2018-11235
• CVE-2018-11776
• CVE-2018-1273