A while ago I stumbled upon an awesome write-up of a very nice CTF challenge created by sapheads:\nhttp:\/\/hackerschool.org\/DefconCTF\/17\/B300.html<\/a><\/p>\nI love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun.<\/p>\nBecause some interesting anti-debugging tricks were implemented into the binary, I decided to make a short video about the reversing process.<\/p>\nFirst of all, thanks to KorUPt and Sapheads (http:\/\/www.sapheads.org) for the awesome cartoon.\nAt the time of creating this video, the binary and KOrUPt's write-up are available here:\nhttp:\/\/www.rohitab.com\/discuss\/index.php?app=core&module=attach§ion=attach&attach_id=2736<\/a><\/p>\nFinally, thanks to Defcon and DDTek for this great challenge !<\/p>\nEnjoy!<\/p>\n <\/p>\nVideo<\/h3>\nYour browser does not support the video tag.<\/video><\/p>\n\n","protected":false},"excerpt":{"rendered":"A while ago I stumbled upon an awesome write-up of a very nice CTF challenge created by sapheads: http:\/\/hackerschool.org\/DefconCTF\/17\/B300.html I love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun. Because some interesting anti-debugging tricks were implemented into the binary...<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[3708,2561,127,2633],"tags":[2802,2676,2619,2308,2128,261],"class_list":["post-6680","post","type-post","status-publish","format-standard","hentry","category-debugging","category-malware-and-reversing","category-security","category-video-security","tag-mona-py","tag-reverse-engineering","tag-anti-debugging","tag-ctf","tag-immunity-debugger","tag-corelan"],"yoast_head":"\nAnti-debugging tricks revealed - Defcon CTF Qualifications 2009: Bin300 Analysis - Corelan | Exploit Development & Vulnerability Research<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.corelan.be\/index.php\/2011\/02\/27\/anti-debugging-tricks-revealed-defcon-ctf-qualifications-2009-bin300-analysis\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Anti-debugging tricks revealed - Defcon CTF Qualifications 2009: Bin300 Analysis - Corelan | Exploit Development & Vulnerability Research\" \/>\n<meta property=\"og:description\" content=\"A while ago I stumbled upon an awesome write-up of a very nice CTF challenge created by sapheads: http:\/\/hackerschool.org\/DefconCTF\/17\/B300.html I love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun. Because some interesting anti-debugging tricks were implemented into the binary...\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.corelan.be\/index.php\/2011\/02\/27\/anti-debugging-tricks-revealed-defcon-ctf-qualifications-2009-bin300-analysis\/\" \/>\n<meta property=\"og:site_name\" content=\"Corelan | Exploit Development & Vulnerability Research\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/corelanconsulting\" \/>\n<meta property=\"article:published_time\" content=\"2011-02-27T16:56:34+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-03-25T08:04:14+00:00\" \/>\n<meta name=\"author\" content=\"Corelan Team (fancy)\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@corelanc0d3r\" \/>\n<meta name=\"twitter:site\" content=\"@corelanc0d3r\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"TechArticle\",\"@id\":\"https:\\\/\\\/www.corelan.be\\\/index.php\\\/2011\\\/02\\\/27\\\/anti-debugging-tricks-revealed-defcon-ctf-qualifications-2009-bin300-analysis\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.corelan.be\\\/index.php\\\/2011\\\/02\\\/27\\\/anti-debugging-tricks-revealed-defcon-ctf-qualifications-2009-bin300-analysis\\\/\"},\"author\":{\"name\":\"Corelan Team (fancy)\",\"@id\":\"https:\\\/\\\/www.corelan.be\\\/#\\\/schema\\\/person\\\/19ac49794ad03a4f053203b956e97513\"},\"headline\":\"Anti-debugging tricks revealed - 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I love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun.<\/p>\n
Because some interesting anti-debugging tricks were implemented into the binary, I decided to make a short video about the reversing process.<\/p>\n
First of all, thanks to KorUPt and Sapheads (http:\/\/www.sapheads.org) for the awesome cartoon.\nAt the time of creating this video, the binary and KOrUPt's write-up are available here:\nhttp:\/\/www.rohitab.com\/discuss\/index.php?app=core&module=attach§ion=attach&attach_id=2736<\/a><\/p>\nFinally, thanks to Defcon and DDTek for this great challenge !<\/p>\nEnjoy!<\/p>\n <\/p>\nVideo<\/h3>\nYour browser does not support the video tag.<\/video><\/p>\n\n","protected":false},"excerpt":{"rendered":"A while ago I stumbled upon an awesome write-up of a very nice CTF challenge created by sapheads: http:\/\/hackerschool.org\/DefconCTF\/17\/B300.html I love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun. Because some interesting anti-debugging tricks were implemented into the binary...<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[3708,2561,127,2633],"tags":[2802,2676,2619,2308,2128,261],"class_list":["post-6680","post","type-post","status-publish","format-standard","hentry","category-debugging","category-malware-and-reversing","category-security","category-video-security","tag-mona-py","tag-reverse-engineering","tag-anti-debugging","tag-ctf","tag-immunity-debugger","tag-corelan"],"yoast_head":"\nAnti-debugging tricks revealed - Defcon CTF Qualifications 2009: Bin300 Analysis - Corelan | Exploit Development & Vulnerability Research<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.corelan.be\/index.php\/2011\/02\/27\/anti-debugging-tricks-revealed-defcon-ctf-qualifications-2009-bin300-analysis\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Anti-debugging tricks revealed - Defcon CTF Qualifications 2009: Bin300 Analysis - Corelan | Exploit Development & Vulnerability Research\" \/>\n<meta property=\"og:description\" content=\"A while ago I stumbled upon an awesome write-up of a very nice CTF challenge created by sapheads: http:\/\/hackerschool.org\/DefconCTF\/17\/B300.html I love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun. 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Finally, thanks to Defcon and DDTek for this great challenge !<\/p>\n
Enjoy!<\/p>\n
<\/p>\n
Your browser does not support the video tag.<\/video><\/p>\n\n","protected":false},"excerpt":{"rendered":"A while ago I stumbled upon an awesome write-up of a very nice CTF challenge created by sapheads: http:\/\/hackerschool.org\/DefconCTF\/17\/B300.html I love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun. 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A while ago I stumbled upon an awesome write-up of a very nice CTF challenge created by sapheads: http:\/\/hackerschool.org\/DefconCTF\/17\/B300.html I love cartoons, and I love reversing, so I decided to play a little bit with that binary (b300.exe) which was a lot of fun. Because some interesting anti-debugging tricks were implemented into the binary...<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[3708,2561,127,2633],"tags":[2802,2676,2619,2308,2128,261],"class_list":["post-6680","post","type-post","status-publish","format-standard","hentry","category-debugging","category-malware-and-reversing","category-security","category-video-security","tag-mona-py","tag-reverse-engineering","tag-anti-debugging","tag-ctf","tag-immunity-debugger","tag-corelan"],"yoast_head":"\n