Home/CVE/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 situatio
CVE

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 situatio

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.

HIGH · CVSS 7.5 EPSS 0.00467
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-755Improper Handling of Exceptional Conditions
▤

Affected Products & Versions

5
haproxy>= 2.2.0 and < 2.2.16
haproxy>= 2.3.0 and < 2.3.13
haproxy>= 2.4.0 and < 2.4.3
debian linuxall versions
fedoraproject fedoraall versions
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD17 Aug 2021 · 07:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
⚑

Vendor Advisories

3
rhsaRHSA-2021:5002Moderate
rhsaRHSA-2021:5208Moderate
rhsaRHSA-2021:4118Moderate
🔗

References & Sources

5
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://git.haproxy.org/?p=haproxy.git
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/
https://www.debian.org/security/2021/dsa-4960Third Party Advisory
https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html
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