CVE-2026-67355

guzzlehttp/guzzle before 7.15.1 Host-only Cookie Scope

MEDIUM
5.9
CVSS Score
Published: August 1, 2026 at 12:22 PM UTC
Updated: October 8, 2026 at 04:17 PM UTC
2 products affected across 2 vendorsGuzzleGuzzle

Using guzzle by guzzle?

Get instant alerts when new vulnerabilities affect guzzle - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM5.9
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 7.15.1
Affected range stops below 7.15.1, so it looks safe — our inference, not a vendor statement
0 ≤ v < 7.15.10
Vendor states this is fixed in 7.15.1 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.9MEDIUMVulnCheck
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-201

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card