p PatchFirst

CVE-2026-55767

CVE-2026-55767 · Guzzle: Dot-Only Cookie Domains Match All Hosts in guzzlehttp/guzzle

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

Guzzle is an extensible PHP HTTP client. Prior to 7.12.1, CookieJar incorrectly accepts cookies with a dot-only Domain attribute and whitespace-padded variants. SetCookie::matchesDomain() removes leading dots from the cookie domain, normalizing dot-only values to the empty string; SetCookie::validate() only rejected a strictly empty domain, so these cookies could be stored and the empty normalized domain was treated as matching any request host. An attacker-controlled origin that an application requests with a shared cookie jar can therefore set a cookie that Guzzle later sends to unrelated hosts using the same jar. This may allow cookie injection or session fixation against downstream services, depending on how those services interpret the injected cookie. This vulnerability is fixed in 7.12.1.

CVSS 5.8 · Medium · EPSS 0.2% · Fix available

Published
Updated

Stack: system · php

Affected products and versions

  • guzzle

    Versions
    • < 7.12.1: Affected

    No fix published

  • guzzle Debian:12

    Versions
    • 7.11.0-1
    • 7.12.0-1
    • 7.12.1-1
    • 7.12.3-1
    • 7.13.1-1
    • 7.14.0-1
    • 7.14.1-1
    • 7.14.2-1
    • 7.15.0-1
    • 7.15.1-1
    • 7.15.2-1
    • 7.15.3-1
    • 7.15.5-1
    • 7.4.5-1
    • 7.9.2-0.1
    • 8.0.1-1
    • 8.0.2-1
    • 8.1.0-1
    • 8.2.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • guzzle Debian:13

    Versions
    • 7.11.0-1
    • 7.12.0-1
    • 7.12.1-1
    • 7.12.3-1
    • 7.13.1-1
    • 7.14.0-1
    • 7.14.1-1
    • 7.14.2-1
    • 7.15.0-1
    • 7.15.1-1
    • 7.15.2-1
    • 7.15.3-1
    • 7.15.5-1
    • 7.9.2-0.1
    • 8.0.1-1
    • 8.0.2-1
    • 8.1.0-1
    • 8.2.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • guzzle Debian:14

    Versions
    • 7.11.0-1
    • 7.12.0-1
    • 7.9.2-0.1
    Affected ranges
    • ECOSYSTEM: < 7.12.1-1

    Update to 7.12.1-1

  • guzzlehttp/guzzle Packagist

    Versions
    • 4.0.0
    • 4.0.0-rc.1
    • 4.0.0-rc.2
    • 4.0.1
    • 4.0.2
    • 4.1.0
    • 4.1.1
    • 4.1.2
    • 4.1.3
    • 4.1.4
    • 4.1.5
    • 4.1.6
    • 4.1.7
    • 4.1.8
    • 4.2.0
    • 4.2.1
    • 4.2.2
    • 4.2.3
    • 4.2.4
    • 5.0.0
    • 5.0.1
    • 5.0.2
    • 5.0.3
    • 5.1.0
    • 5.2.0
    • 5.3.0
    • 5.3.1
    • 5.3.2
    • 5.3.3
    • 5.3.4
    • 6.0.0
    • 6.0.1
    • 6.0.2
    • 6.1.0
    • 6.1.1
    • 6.2.0
    • 6.2.1
    • 6.2.2
    • 6.2.3
    • 6.3.0
    • 6.3.1
    • 6.3.2
    • 6.3.3
    • 6.4.0
    • 6.4.1
    • 6.5.0
    • 6.5.1
    • 6.5.2
    • 6.5.3
    • 6.5.4
    • 6.5.5
    • 6.5.6
    • 6.5.7
    • 6.5.8
    • 7.0.0
    • 7.0.0-beta.1
    • 7.0.0-beta.2
    • 7.0.0-rc.1
    • 7.0.1
    • 7.1.0
    • 7.1.1
    • 7.10.0
    • 7.10.1
    • 7.10.2
    • 7.10.3
    • 7.10.4
    • 7.10.5
    • 7.10.6
    • 7.11.0
    • 7.11.1
    • 7.11.2
    • 7.12.0
    • 7.2.0
    • 7.3.0
    • 7.4.0
    • 7.4.1
    • 7.4.2
    • 7.4.3
    • 7.4.4
    • 7.4.5
    • 7.5.0
    • 7.5.1
    • 7.5.2
    • 7.5.3
    • 7.6.0
    • 7.6.1
    • 7.7.0
    • 7.7.1
    • 7.8.0
    • 7.8.1
    • 7.8.2
    • 7.9.0
    • 7.9.1
    • 7.9.2
    • 7.9.3
    • v1.0.3
    • v1.0.4
    • v2.0.0
    • v2.0.1
    • v2.0.2
    • v2.0.3
    • v2.0.4
    • v2.0.5
    • v2.1.0
    • v2.1.1
    • v2.1.2
    • v2.1.3
    • v2.1.4
    • v2.2.0
    • v2.2.1
    • v2.2.2
    • v2.2.3
    • v2.2.4
    • v2.3.2
    • v2.4.0
    • v2.4.1
    • v2.5.0
    • v2.6.0
    • v2.6.1
    • v2.6.2
    • v2.6.3
    • v2.6.4
    • v2.6.5
    • v2.6.6
    • v2.7.0
    • v2.7.1
    • v2.7.2
    • v2.8.0
    • v2.8.1
    • v2.8.2
    • v2.8.3
    • v2.8.4
    • v2.8.5
    • v2.8.6
    • v2.8.7
    • v2.8.8
    • v3.0.0
    • v3.0.1
    • v3.0.2
    • v3.0.3
    • v3.0.4
    • v3.0.5
    • v3.0.6
    • v3.0.7
    • v3.1.0
    • v3.1.1
    • v3.1.2
    • v3.2.0
    • v3.3.0
    • v3.3.1
    • v3.4.0
    • v3.4.1
    • v3.4.2
    • v3.4.3
    • v3.5.0
    • v3.6.0
    • v3.7.0
    • v3.7.1
    • v3.7.2
    • v3.7.3
    • v3.7.4
    • v3.8.0
    • v3.8.1
    Affected ranges
    • ECOSYSTEM: < 7.12.1

    Update to 7.12.1

  • guzzle Ubuntu:24.04:LTS

    Versions
    • 7.4.5-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • guzzle Ubuntu:25.10

    Versions
    • 7.9.2-0.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • guzzle Ubuntu:26.10

    Versions
    • 7.9.2-0.1build1
    • 7.13.1-1
    • 7.15.1-1
    • 7.15.2-1
    • 7.15.3-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • guzzle Ubuntu:26.04:LTS

    Versions
    • 7.9.2-0.1
    • 7.9.2-0.1build1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

Check your server →