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CVE-2016-4554

HIGH severity · CVSS 8.6 · CWE-345
8.6CVSS HIGH

Summary

mime_header.cc in Squid before 3.5.18 allows remote attackers to bypass intended same-origin restrictions and possibly conduct cache-poisoning attacks via a crafted HTTP Host header, aka a "header smuggling" issue.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactHigh
Availability impactNone
Exploit probability (EPSS)39%

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

Affected products we track (1)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Official patch: http://www.squid-cache.org/Versions/v3/3.1/changesets/SQUID-2016_8.patch ↗