1549.txt

snort入侵检测规则文件2.4 Snort是众所周知的网络入侵检测工具

Rule:

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Sid:

1549

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Summary:
This event is generated when an attempt is made to overflow a buffer in an SMTP server via a long SMTP HELO command. 

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Impact:
A remote attacker could exploit this vulnerability to cause a denial of service, or possibly execute arbitrary code.

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Detailed Information:
Most SMTP servers do not properly validate the input string. A buffer overflow may occur when an attacker use a HELO command followed by 1024+ characters. If the server is vulnerable ,it will crash or close the connection, otherwise it will give an error message.

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Affected Systems:

	SMTP servers Any version
	AppleShare IP Mail Server Any version
	Mercury Mail Server Any version
	SLMail v2.6 and earlier
	

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Attack Scenarios:
telnet victim.foo.com 25
helo victim
220 victim SMTP Server Ready 
HELO XXXXXXXXXXX[a thousand of these]XXXXXXXX 

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Ease of Attack:
Simple.

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False Positives:
None known.

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False Negatives:
None known.

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Corrective Action:
Upgrade to the latest non-affected version of the software

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Contributors:

Sourcefire Research Team
Brian Caswell <[e-mail]>
Nigel Houghton <[e-mail]>
Snort documentation contributed by Nawapong Nakjang ([e-mail], [e-mail])

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Additional References:

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