Description
HAProxy 2.9.x before 2.9.10, 3.0.x before 3.0.4, and 3.1.x through 3.1-dev6 allows a remote denial of service for HTTP/2 zero-copy forwarding (h2_send loop) under a certain set of conditions, as exploited in the wild in 2024.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | haproxy | 2.9.10-1 | — |
| Debian 13 | haproxy | 2.9.10-1 | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | haproxy | 3.0.4+git0.7a59afa93-1.1 | openSUSE-SU-2024:14307-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | haproxy | 2.9.11-1 | — |
Advisories 2
- openSUSE-SU-2024:14307-1 haproxy-3.0.4+git0.7a59afa93-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2024-2050 HAProxy Enterprise und ALOHA: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Oct 22, 2024
References
- https://www.haproxy.org/
- https://www.haproxy.org/download/3.1/src/CHANGELOG
- https://www.mail-archive.com/haproxy%40formilux.org/msg45281.html
- https://www.mail-archive.com/haproxy%40formilux.org/msg45280.html
- http://git.haproxy.org/?p=haproxy-3.0.git%3Ba=commitdiff%3Bh=c725db17e8416ffb3c1537aea756356228ce5e3c
- http://git.haproxy.org/?p=haproxy-3.0.git%3Ba=commitdiff%3Bh=d636e515453320c6e122c313c661a8ac7d387c7f