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.
References2
Metrics
- CVSS 3.1
-
5.9
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 4.0
-
8.2
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 31 · as of 13 November 2026
- CWE
- CWE-201
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