It is possible to stash malware e.g. bo2k.exe in a zip file and use the DOS copy command to prepend some innocuous jpg. "copy apic.jpg + bo2k.zip bo2k.jpg /b". The resultant file renders as a jpg in IE, but the jpg part is completely ignored when you open as an archive under winzip. This doesn't mean that an unsuspecting user could trigger the malware, but it does mean that malware can be easily moved around an organisation under the guise of some innocuous jpg. This technique has been used for some time for the purposes of disguising pirate software. -------------------------------- Pete Simpson Threat Lab Manager Research Department Baltimore Technologies Content Security Group -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6.3ia mQCNAzoe8V4AAAEEAL/Gi1BY8zY0E0uLDdvCN/J2D/pD492iFIVi9GeWWz1QbLo2 f/YKnGVeKsTYjWQHfFh4fKDpzHgC/Ufmswf4a74C/jQQ/buw8X+wWSTzsZ2W2ZaV jMVLj969ZopoHiv4yoNtb+m4erbvthfQbabhDZES5RHl3Qj/k+Z175sVOEblAAUR tBJDb250ZW50IFRocmVhdCBMYWKJAJUDBRA6HvFe5nXvmxU4RuUBASSHA/wLM+kk +a+Bdt3AyRV5UCQQf/yyvCdDKEZqM5q9SqO6sR13GF4kMbRY/7/ZS+/0f98IjplZ er9mpblsJcM60yeWmV+LnxDo2eEZgTHW8h65pZRT6QYHAgXFBAKpV4D5AH8aV5S4 HrK7aShzXNGNcQRiBoUU7ELP/CgXlqD41J6NQA== =qsME -----END PGP PUBLIC KEY BLOCK----- ----------------------------------------------------------------------------------------------------------------- The information contained in this message is confidential and is intended for the addressee(s) only. If you have received this message in error or there are any problems please notify the originator immediately. The unauthorized use, disclosure, copying or alteration of this message is strictly forbidden. Baltimore Technologies plc will not be liable for direct, special, indirect or consequential damages arising from alteration of the contents of this message by a third party or as a result of any virus being passed on. This footnote confirms that this email message has been swept by Baltimore MIMEsweeper for Content Security threats, including computer viruses.
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