CVE-2026-26080

HAProxy Community Edition 3.2.x through 3.3.x before 3.3.3 can enter a loop or crash because...

3.7 LowPublic exploitFix available

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: High
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: Low

Exploit likelihood

0.55%Up 0.1 points since Jul 21, 2026

What each source reports

CVE List Score used 3.7

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.

Record: CVE-2026-26080
CVSS 3.1: 3.7 LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness: CWE-252
Updated: 2026-11-02

EUVDEUVD-2026-45988 3.7

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.

Record: EUVD-2026-45988
CVSS 3.1: 3.7 LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Updated: 2026-11-02

GitHub AdvisoriesGHSA-fhrv-3q89-79q6 3.7

HAProxy Community Edition 3.2.x through 3.3.x before 3.3.3 can enter a loop or crash because...

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.

Record: GHSA-fhrv-3q89-79q6
CVSS 3.1: 3.7 LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness: CWE-252
Updated: 2026-11-02

NVD 3.7

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.

Record: CVE-2026-26080
CVSS 3.1: 3.7 LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness: CWE-252
Updated: 2026-11-02

OSV 3.7

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.

Record: CVE-2026-26080
CVSS 3.1: 3.7 LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness: CWE-252
Updated: 2026-11-02

OSVDEBIAN-CVE-2026-26080 3.7

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.

Record: DEBIAN-CVE-2026-26080
CVSS 3.1: 3.7 LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Updated: 2026-11-02

Show 6 moreShow less

OSVRHSA-2026:40938 5.9

Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update

Record: RHSA-2026:40938
CVSS 3.1: 5.9 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVBIT-haproxy-2026-26080 No score

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.

Record: BIT-haproxy-2026-26080
Updated: 2026-11-02

OSVopenSUSE-SU-2026:20290-1 No score

Security update for haproxy

This update for haproxy fixes the following issues:

Update to version 3.2.12+git0.6011f448e
CVE-2026-26081: Fixed a DOS vulnerability in QUIC. (bsc#1257976)
CVE-2026-26080: Fixed a DOS vulnerability in QUIC. (bsc#1257976)

Record: openSUSE-SU-2026:20290-1
Updated: 2026-11-02

OSVSUSE-SU-2026:20557-1 No score

Security update for haproxy

This update for haproxy fixes the following issues:

Update to version 3.2.12+git0.6011f448e
CVE-2026-26081: Fixed a DOS vulnerability in QUIC. (bsc#1257976)
CVE-2026-26080: Fixed a DOS vulnerability in QUIC. (bsc#1257976)

Record: SUSE-SU-2026:20557-1
Updated: 2026-11-02

OSVSUSE-SU-2026:20616-1 No score

Security update for haproxy

This update for haproxy fixes the following issues:

Update to version 3.2.12+git0.6011f448e
CVE-2026-26081: Fixed a DOS vulnerability in QUIC. (bsc#1257976)
CVE-2026-26080: Fixed a DOS vulnerability in QUIC. (bsc#1257976)

Record: SUSE-SU-2026:20616-1
Updated: 2026-11-02

OSVSUSE-SU-2026:20620-1 No score

Security update for haproxy

This update for haproxy fixes the following issues:

Update to version 3.2.12+git0.6011f448e
CVE-2026-26081: Fixed a DOS vulnerability in QUIC. (bsc#1257976)
CVE-2026-26080: Fixed a DOS vulnerability in QUIC. (bsc#1257976)

Record: SUSE-SU-2026:20620-1
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`haproxy` Bitnami	3.2.0 up to 3.2.12, 3.3.0 up to 3.3.3	3.2.123.3.3
`haproxy` Debian:14	before 3.2.11-2, plus listed versions 3.0.11-13.1.0-13.1.0-23.1.1-13.1.2-1 Show 17 moreShow less 3.1.3-13.1.5-13.1.6-13.1.7-13.2.0-13.2.1-13.2.10-13.2.11-13.2.3-13.2.3-23.2.4-13.2.5-13.2.5-23.2.6-13.2.7-13.2.8-13.2.9-1	3.2.11-2
`haproxy` Red Hat:hummingbird:1 From an advisory covering 2 CVEs	before 0:3.0.25-0.1.1.hum1	0:3.0.25-0.1.1.hum1
`haproxy` SUSE:Linux Micro 6.2 From an advisory covering 2 CVEs	before 3.2.12+git0.6011f448e-160000.1.1	3.2.12+git0.6011f448e-160000.1.1
`haproxy` SUSE:Linux Enterprise High Availability Extension 16.0 From an advisory covering 2 CVEs	before 3.2.12+git0.6011f448e-160000.1.1	3.2.12+git0.6011f448e-160000.1.1
`haproxy` SUSE:Linux Enterprise Server for SAP applications 16.0 From an advisory covering 2 CVEs	before 3.2.12+git0.6011f448e-160000.1.1	3.2.12+git0.6011f448e-160000.1.1
`haproxy` openSUSE:Leap 16.0 From an advisory covering 2 CVEs	before 3.2.12+git0.6011f448e-160000.1.1	3.2.12+git0.6011f448e-160000.1.1

Public exploits

Links only. Every CVE stores no exploit code.

Public exploits
Source	Link	Date
PoC in GitHub	Zeerg/haproxy-quic-cves-2026	2026-10-27

History

History
Recorded	Changed	Sources
Nov 6, 2026	affected, facts
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV, PoC in GitHub

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-26080 is a low vulnerability (CVSS 3.7) in Haproxy Aloha, published February 27, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.55%, the 46th percentile. Fixed in haproxy 3.2.12.

References

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