SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-39242

It can lead to a situation with an attacker-controlled HTTP Host header, because a mismatch between Host and authority is mishandled.

HIGH 7.5EPSS 2.34%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (2.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
2.34% probability · 83th percentile
CISA KEV
Not listed
Weakness
CWE-755
Affected
haproxy/haproxy · debian/debian linux · fedoraproject/fedora
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.