High severity · published Aug 17, 2021
CVE-2021-39242
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
7.5
CVSS
2.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.2% · higher than 83% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
11.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
HA
Haproxy · Haproxy
2.2.0 before 2.2.16; 2.3.0 before 2.3.13; 2.4.0 before 2.4.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-39242
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-39242
git.haproxy.org
https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=b5d2b9e154d78e4075db163826c5e0f6d31b2ab1
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/
Third Party Advisory
https://www.debian.org/security/2021/dsa-4960
www.mail-archive.com
https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html
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