What’s Vulnerable › Vulnerabilities

CVE-2026-59883: Guzzle: Cookie Disclosure and Injection via IP-Address Domains

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-08 · updated 2026-07-13
• Weakness: CWE-346

Description

Guzzle is an extensible PHP HTTP client. Prior to 7.12.3, CookieJar did not restrict cookies scoped to IP-address or bare-numeric Domain values to the exact host that set them, because SetCookie::matchesDomain() applied ordinary suffix matching to domains such as 192.168.0.1, [::1], or 1, allowing cross-host cookie disclosure, cookie injection, or session fixation. This issue is fixed in version 7.12.3.

Affected products

• guzzle: before 7.12.3 — fixed in 7.12.3
• Packagist Guzzlehttp/Guzzle: before 7.12.3; 4.0.0, 4.0.0-rc.1, 4.0.0-rc.2, 4.0.1, 4.0.2, 4.1.0 (+159) — fixed in 7.12.3

How to fix

Upgrade to a fixed version: guzzle 7.12.3; Packagist Guzzlehttp/Guzzle 7.12.3. Check the vendor advisory for mitigations.

References

• https://github.com/guzzle/guzzle/commit/b9944c161b12d9ee9c9334cfc5b9659ecd7451f8
• https://github.com/guzzle/guzzle/pull/3694
• https://github.com/guzzle/guzzle/releases/tag/7.12.3
• https://github.com/guzzle/guzzle/security/advisories/GHSA-g446-98w2-8p5w

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