CVE-2021-39242
7.5 HIGHAn issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3
Published: 2021-08-17 · Last updated: 2026-06-17
Severity and scoring
- CVSS
- 7.5 HIGH
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- CWE
- CWE-755
Affected products
| Vendor | Product |
|---|---|
| debian | debian_linux, fedora, haproxy |
| fedoraproject | debian_linux, fedora, haproxy |
| haproxy | debian_linux, fedora, haproxy |
Description
An issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. It can lead to a situation with an attacker-controlled HTTP Host header, because a mismatch between Host and authority is mishandled.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-39242
- [Other]https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=b5d2b9e154d78e4075db163826c5e0f6d31b2ab1
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/
- [Other]https://www.debian.org/security/2021/dsa-4960
- [Other]https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html
- [Other]https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=b5d2b9e154d78e4075db163826c5e0f6d31b2ab1
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/
- [Other]https://www.debian.org/security/2021/dsa-4960
- [Other]https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html
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