CVE-2006-1242

Severity: medium (CVSS 5.0 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: 2006-03-15 · updated 2026-06-16

Description

The ip_push_pending_frames function in Linux 2.4.x and 2.6.x before 2.6.16 increments the IP ID field when sending a RST after receiving unsolicited TCP SYN-ACK packets, which allows remote attackers to conduct an Idle Scan (nmap -sI) attack, which bypasses intended protections against such attacks.

Affected products

Linux kernel: 2.4.0, 2.4.0-test1, 2.4.0-test10, 2.4.0-test11, 2.4.0-test12, 2.4.0-test2 (+149)

References

http://secunia.com/advisories/19402
http://secunia.com/advisories/19955
http://secunia.com/advisories/20157
http://secunia.com/advisories/20398
http://secunia.com/advisories/20671
http://secunia.com/advisories/20914
http://secunia.com/advisories/21136
http://secunia.com/advisories/21465
http://secunia.com/advisories/21983
http://secunia.com/advisories/22417
http://support.avaya.com/elmodocs2/security/ASA-2006-180.htm
http://support.avaya.com/elmodocs2/security/ASA-2006-200.htm

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