3.7Low

Haproxy Haproxy

CVE-2026-26080

HAProxy Community Edition 3.2.x through 3.3.x before 3.3.3 can enter a loop or crash because varint is mishandled. HAProxy Enterprise and ALOHA are also affected.

What this means for your business

  • It affects Haproxy. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.

What to do

  1. 1Check whether your company or your suppliers run Haproxy, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
3.7 (v3.1)
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness
CWE-252
Assigned by
cve@mitre.org

Dates

Published
2026-07-20
Last modified
2026-08-25
Sources
NVD

Affected products

  • Haproxy Haproxy3.2 - 3.2.12, 3.3 - 3.3.3
  • Haproxy Aloha17.0.0 - 17.0.18, 17.5.0 - 17.5.16
  • Haproxy Haproxy Enterprise3.2r1

As listed in the NVD configuration data. Not a statement about your estate.

References