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CVE-2026-110354

CVE-2026-110354

This page contains facts from public vulnerability sources. Check the original advisory before updating.

HAProxy 3 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (persistent worker-thread CPU exhaustion) via an HTTP/1.1 chunked request. Although the H1 multiplexer drains the request before closing the stream, the parser repeatedly re-processes the same bytes without making progress. The affected thread stays busy at 100% CPU after timeouts expire and after the client disconnects, and repeated requests can consume all worker threads until the process is restarted.

CVSS 7.5 · High · EPSS 0.8% · Fix available

Published
Updated

Stack: system · web

Affected products and versions

  • haproxy

    Versions
    • ≥ 3.0.0, < 3.0.30: Affected (custom)
    • ≥ 3.2.0, < 3.2.26: Affected (custom)
    • ≥ 3.3.0, < 3.3.17: Affected (custom)
    • ≥ 3.4.0, < 3.4.6: Affected (custom)
    • ≥ 3.5-dev, < 3.5-dev9: Affected (custom)

    Update to 3.0.30; Update to 3.2.26; Update to 3.3.17; Update to 3.4.6; Update to 3.5-dev9

  • haproxy enterprise edition

    Versions
    • ≥ 3.0r1, < 3.0r1-362.1441: Affected (custom)
    • ≥ 3.2r1, < 3.2r1-378.1259: Affected (custom)
    • ≥ 3.3r1, < 3.3r1-377.1005: Affected (custom)

    No fix published

  • haproxy kubernetes ingress controller

    Versions
    • ≥ 3.2.0, < 3.2.17: Affected (custom)

    Update to 3.2.17

  • kubernetes ingress controller enterprise

    Versions
    • ≥ 3.2.0, < 3.2.17-ee1: Affected (custom)
    • ≥ 3.0, < 3.0.16-ee17: Affected (custom)
    • ≥ 1.11, < 1.11.14-ee11: Affected (custom)

    Update to 1.11.14-ee11; Update to 3.0.16-ee17; Update to 3.2.17-ee1

  • haproxy Ubuntu:Pro:16.04:LTS

    Versions
    • 1.5.14-1
    • 1.5.15-1
    • 1.6.2-1
    • 1.6.2-2
    • 1.6.2-2ubuntu1
    • 1.6.2-2ubuntu3
    • 1.6.3-1
    • 1.6.3-1ubuntu0.1
    • 1.6.3-1ubuntu0.2
    • 1.6.3-1ubuntu0.3
    • 1.6.3-1ubuntu0.3+esm1
    • 1.6.3-1ubuntu0.3+esm2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • haproxy Ubuntu:Pro:18.04:LTS

    Versions
    • 1.7.9-1ubuntu1
    • 1.7.9-1ubuntu2
    • 1.8.4-1
    • 1.8.7-1
    • 1.8.8-1
    • 1.8.8-1ubuntu0.1
    • 1.8.8-1ubuntu0.2
    • 1.8.8-1ubuntu0.3
    • 1.8.8-1ubuntu0.4
    • 1.8.8-1ubuntu0.6
    • 1.8.8-1ubuntu0.7
    • 1.8.8-1ubuntu0.8
    • 1.8.8-1ubuntu0.9
    • 1.8.8-1ubuntu0.10
    • 1.8.8-1ubuntu0.11
    • 1.8.8-1ubuntu0.13
    • 1.8.8-1ubuntu0.13+esm2
    • 1.8.8-1ubuntu0.13+esm3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • haproxy Ubuntu:20.04:LTS

    Versions
    • 2.0.5-1
    • 2.0.8-1
    • 2.0.9-1
    • 2.0.10-1
    • 2.0.10-1ubuntu1
    • 2.0.11-1ubuntu1
    • 2.0.12-1ubuntu2
    • 2.0.13-1ubuntu2
    • 2.0.13-2
    • 2.0.13-2ubuntu0.1
    • 2.0.13-2ubuntu0.2
    • 2.0.13-2ubuntu0.3
    • 2.0.13-2ubuntu0.5
    • 2.0.29-0ubuntu1
    • 2.0.29-0ubuntu1.1
    • 2.0.29-0ubuntu1.3
    • 2.0.31-0ubuntu0.1
    • 2.0.31-0ubuntu0.2
    • 2.0.31-0ubuntu0.3
    • 2.0.33-0ubuntu0.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • haproxy Ubuntu:22.04:LTS

    Versions
    • 2.2.9-2ubuntu2
    • 2.4.8-1
    • 2.4.8-2ubuntu3
    • 2.4.11-1ubuntu1
    • 2.4.12-1ubuntu1
    • 2.4.12-1ubuntu2
    • 2.4.13-1ubuntu1
    • 2.4.14-1ubuntu1
    • 2.4.18-0ubuntu1
    • 2.4.18-0ubuntu1.1
    • 2.4.18-0ubuntu1.2
    • 2.4.18-0ubuntu1.3
    • 2.4.22-0ubuntu0.22.04.1
    • 2.4.22-0ubuntu0.22.04.2
    • 2.4.22-0ubuntu0.22.04.3
    • 2.4.24-0ubuntu0.22.04.1
    • 2.4.24-0ubuntu0.22.04.2
    • 2.4.24-0ubuntu0.22.04.3
    • 2.4.29-0ubuntu0.22.04.1
    • 2.4.30-0ubuntu0.22.04.1
    • 2.4.30-0ubuntu0.22.04.2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • haproxy Ubuntu:24.04:LTS

    Versions
    • 2.6.15-1ubuntu2
    • 2.8.5-1ubuntu1
    • 2.8.5-1ubuntu2
    • 2.8.5-1ubuntu3
    • 2.8.5-1ubuntu3.1
    • 2.8.5-1ubuntu3.2
    • 2.8.5-1ubuntu3.3
    • 2.8.5-1ubuntu3.4
    • 2.8.15-0ubuntu0.24.04.1
    • 2.8.16-0ubuntu0.24.04.1
    • 2.8.16-0ubuntu0.24.04.2
    • 2.8.16-0ubuntu0.24.04.3
    • 2.8.30-0ubuntu0.24.04.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • haproxy Ubuntu:26.10

    Versions
    • 3.2.9-1ubuntu2
    • 3.2.9-1ubuntu2.1
    • 3.2.9-1ubuntu3
    • 3.4.2-1ubuntu2
    • 3.4.2-1ubuntu3
    • 3.4.2-1ubuntu4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • haproxy Ubuntu:26.04:LTS

    Versions
    • 3.0.10-1ubuntu3
    • 3.2.9-1ubuntu1
    • 3.2.9-1ubuntu2
    • 3.2.9-1ubuntu2.1
    • 3.2.9-1ubuntu2.2
    • 3.2.25-0ubuntu0.26.04.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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