High severity · published Aug 17, 2021
CVE-2021-39240
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 does not ensure that the scheme and path portions of a URI have the expected characters. For example, the authority field (as observed on a target HTTP/2 server) might differ from what the routing rules were intended to achieve.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
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-2021-39240
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-39240
git.haproxy.org
https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=4b8852c70d8c4b7e225e24eb58258a15eb54c26e
git.haproxy.org
https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=a495e0d94876c9d39763db319f609351907a31e8
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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