Vulnerability in Haproxy

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. 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.

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:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.022 (81.5th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 81.5% 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-2021-39240: held from 0.023 to 0.022.

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

Affected products

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-39240?
CVE-2021-39240 is a high-severity vulnerability in Haproxy. CVSS score: 7.5/10. Published 2021-08-17.
How severe is CVE-2021-39240?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2021-39240 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.