Vulnerability in Haproxy

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

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.022 (81.7th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 81.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-39242: held from 0.023 to 0.022.

EPSS over last 30 days · oldest: 0.023 · newest: 0.022 · change: -0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-39242?
CVE-2021-39242 is a high-severity vulnerability in Haproxy, classified under Improper Handling of Exceptional Conditions. CVSS score: 7.5/10. Published 2021-08-17.
How severe is CVE-2021-39242?
High severity. CVSS v3 base score is 7.5 out of 10.