What’s Vulnerable › Vulnerabilities

CVE-2011-1093

• Severity: high (CVSS 7.8 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2011-07-18 · updated 2026-06-16
• Weakness: CWE-476

Description

The dccp_rcv_state_process function in net/dccp/input.c in the Datagram Congestion Control Protocol (DCCP) implementation in the Linux kernel before 2.6.38 does not properly handle packets for a CLOSED endpoint, which allows remote attackers to cause a denial of service (NULL pointer dereference and OOPS) by sending a DCCP-Close packet followed by a DCCP-Reset packet.

Affected products

• Linux kernel: before 2.6.38 — fixed in 2.6.38
• RedHat Enterprise Linux Aus: 5.6
• RedHat Enterprise Linux Desktop: 5.0
• RedHat Enterprise Linux Eus: 5.6
• RedHat Enterprise Linux Server: 5.0
• RedHat Enterprise Linux Workstation: 5.0

How to fix

Upgrade to a fixed version: Linux kernel 2.6.38. Check the vendor advisory for mitigations.

References

• http://downloads.avaya.com/css/P8/documents/100145416
• http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=720dc34bbbe9493c7bd48b2243058b4e447a929d
• http://openwall.com/lists/oss-security/2011/03/08/19
• http://openwall.com/lists/oss-security/2011/03/08/4
• http://rhn.redhat.com/errata/RHSA-2011-0833.html
• http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.38
• http://www.securityfocus.com/bid/46793
• https://bugzilla.redhat.com/show_bug.cgi?id=682954
• http://downloads.avaya.com/css/P8/documents/100145416
• http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=720dc34bbbe9493c7bd48b2243058b4e447a929d
• http://openwall.com/lists/oss-security/2011/03/08/19
• http://openwall.com/lists/oss-security/2011/03/08/4

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