Restricted-port access via late request blocking
Published Sep 8, 2021 · Updated Aug 3, 2024
Restricted-port bypass in Apple WebKit allows remote attackers to send requests to restricted ports by luring a user to a malicious website. WebKit sends an initial form POST to a prohibited destination before enforcing the port restriction, then blocks only display of the response. User interaction with crafted web content is required; the attacker can deliver protocol data to sensitive non-HTTP services but cannot read their responses through this flaw.
Summary
What happened
Restricted-port bypass in Apple WebKit allows remote attackers to send requests to restricted ports by luring a user to a malicious website. WebKit sends an initial form POST to a prohibited destination before enforcing the port restriction, then blocks only display of the response. User interaction with crafted web content is required; the attacker can deliver protocol data to sensitive non-HTTP services but cannot read their responses through this flaw.
The record
- CVE
- CVE-2021-30720
- Published
- Sep 8, 2021
- Updated
- Aug 3, 2024
- Vendor
- Apple
- Product
- iOS and iPadOS
- Classifications
- CWE-287
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 8, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=unspecified <14.6
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Restricted-port form POST proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo