Medium severity · published Aug 1, 2026
CVE-2026-67355
guzzlehttp/guzzle before 7.15.1 Host-only Cookie Scope
5.9
CVSS
0.4%
EPSS
No
On KEV
Description
guzzlehttp/guzzle versions before 7.15.1 fail to preserve host-only cookie scope, storing the request host in the Domain field instead of marking cookies as host-only. Attackers controlling child hosts can receive host-only cookies intended only for parent hosts, potentially disclosing session identifiers and authorization tokens when the same cookie jar is reused across trust boundaries.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GU
guzzle · guzzle
before 7.15.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-67355
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-67355
vendor-advisory
https://github.com/guzzle/guzzle/security/advisories/GHSA-wm3w-8rrp-j577
third-party-advisory
https://www.vulncheck.com/advisories/guzzlehttp-guzzle-before-host-only-cookie-scope
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