Firewall bypass via misparsed IRC DCC messages
Published Sep 1, 2022 · Updated Aug 3, 2024
Improper IRC message parsing in Linux Kernel nf_conntrack_irc allows remote attackers to bypass firewall filtering through crafted DCC traffic. The helper scans an outbound TCP stream for a DCC marker outside the proper IRC message position and compares its supplied address with the IRC server rather than the NAT host. Exploitation requires unencrypted IRC and an enabled IRC conntrack helper; it can expose ports behind NAT or disconnect the IRC user with port zero.
Summary
What happened
Improper IRC message parsing in Linux Kernel nf_conntrack_irc allows remote attackers to bypass firewall filtering through crafted DCC traffic. The helper scans an outbound TCP stream for a DCC marker outside the proper IRC message position and compares its supplied address with the IRC server rather than the NAT host. Exploitation requires unencrypted IRC and an enabled IRC conntrack helper; it can expose ports behind NAT or disconnect the IRC user with port zero.
The record
- CVE
- CVE-2022-2663
- Published
- Sep 1, 2022
- Updated
- Aug 3, 2024
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- Unavailable
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 1, 2022CVE 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
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Is a vulnerable build present?
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- Affected versionversion=unknown
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
- NAT-Again crafted CTCP PING demonstrationfunctional · demonstrated
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Technologies
Your stack
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Your stack
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