Integer overflow in Haproxy
CVE-2021-40346
An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, allowing an attacker to bypass all configured http-request HAProxy ACLs and possibly other ACLs.
Vulnerability class: Integer Overflow
EPSS: 0.579 (99.0th percentile) — read the EPSS interpretation.
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.
Affected products
- Haproxy — versions 2.5
- Debian Debian_linux — versions 11.0
- Fedoraproject Fedora — versions 33, 34
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (x_refsource_MISC)
- cve@mitre.org (Patch, x_refsource_MISC, Vendor Advisory)
- cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
- cve@mitre.org (x_refsource_MISC)
- cve@mitre.org (Exploit, Third Party Advisory, x_refsource_MISC, Mitigation)
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (mailing-list, x_refsource_MLIST)
- cve@mitre.org (mailing-list, x_refsource_MLIST)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
Frequently asked questions
- What is CVE-2021-40346?
- CVE-2021-40346 is a high-severity vulnerability in Haproxy, classified under Integer Overflow or Wraparound. CVSS score: 7.5/10. Published 2021-09-08.
- How severe is CVE-2021-40346?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2021-40346 known to be exploited?
- 27 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.