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… (CVE-2026-67355)
guzzlehttp/guzzle versions before 7.15.1 have a vulnerability where host-only cookies are not properly preserved. Instead of marking cookies as host-only, the request host is stored in the Domain field. This flaw allows attackers controlling child hosts to access host-only cookies intended for parent hosts, potentially exposing session identifiers and authorization tokens if the same cookie jar is reused across trust boundaries.
AI Analysis
Technical Summary
The vulnerability in guzzlehttp/guzzle prior to version 7.15.1 involves improper handling of host-only cookie scope. The library incorrectly stores the request host in the Domain attribute of cookies rather than marking them as host-only. This misconfiguration can lead to cookies being accessible to subdomains (child hosts) that should not have access, risking disclosure of sensitive session and authorization information. The CVSS 3.1 score is 5.9 (medium-high severity) with network attack vector, high attack complexity, no privileges required, no user interaction, unchanged scope, and high confidentiality impact but no integrity or availability impact. There are no known exploits in the wild and no patch links provided in the data.
Potential Impact
Attackers controlling child hosts can receive host-only cookies meant exclusively for parent hosts. This can lead to unauthorized disclosure of session identifiers and authorization tokens, increasing the risk of session hijacking or unauthorized access when cookie jars are reused across trust boundaries. The vulnerability affects confidentiality but does not impact integrity or availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch links or official fixes are provided in the data, users should monitor vendor communications for updates. Until a fix is available, avoid reusing cookie jars across trust boundaries and restrict cookie sharing to trusted domains only.
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… (CVE-2026-67355)
Description
guzzlehttp/guzzle versions before 7.15.1 have a vulnerability where host-only cookies are not properly preserved. Instead of marking cookies as host-only, the request host is stored in the Domain field. This flaw allows attackers controlling child hosts to access host-only cookies intended for parent hosts, potentially exposing session identifiers and authorization tokens if the same cookie jar is reused across trust boundaries.
CVSS v3.1
Score 5.9medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in guzzlehttp/guzzle prior to version 7.15.1 involves improper handling of host-only cookie scope. The library incorrectly stores the request host in the Domain attribute of cookies rather than marking them as host-only. This misconfiguration can lead to cookies being accessible to subdomains (child hosts) that should not have access, risking disclosure of sensitive session and authorization information. The CVSS 3.1 score is 5.9 (medium-high severity) with network attack vector, high attack complexity, no privileges required, no user interaction, unchanged scope, and high confidentiality impact but no integrity or availability impact. There are no known exploits in the wild and no patch links provided in the data.
Potential Impact
Attackers controlling child hosts can receive host-only cookies meant exclusively for parent hosts. This can lead to unauthorized disclosure of session identifiers and authorization tokens, increasing the risk of session hijacking or unauthorized access when cookie jars are reused across trust boundaries. The vulnerability affects confidentiality but does not impact integrity or availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch links or official fixes are provided in the data, users should monitor vendor communications for updates. Until a fix is available, avoid reusing cookie jars across trust boundaries and restrict cookie sharing to trusted domains only.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-mjrx-74jh-7xgw
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-67355"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a6e6290bf32cb7a344f5e18
Added to database: 08/01/2026, 21:18:08 UTC
Last enriched: 08/01/2026, 21:19:31 UTC
Last updated: 08/01/2026, 22:37:57 UTC
Views: 2
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