Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b52bfca4bac3776…

MALICIOUS

PDF

88.5 KB Created: 2021-06-27 09:59:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 40dac7ec6d85323ada55d08b21d76eb4 SHA-1: abddc2fd48c174a61cb2d9ccad71ae77db11d622 SHA-256: 3b52bfca4bac37766edd4da102525a936b2be3562b5097ee13de49f3202e213d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting. The embedded document body is unreadable, but the presence of many external links suggests an attempt to redirect users to malicious sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://happyhanool.com/ckupload/files/10640227872.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec45c8326c---jojavavegepagora.pdf
    • http://nfc.soo.jp/file/fejofaxiwavojogiluna.pdf
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/992e1deaed02074ab96226eb72c2532f/gabomugize.pdf
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/389710392c92edf9189136fce28d5264/38065256108.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c906a149ab---60589316173.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb282389ab---lidonafawukatot.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/df3db22d2ebd13a4d20022552f564df5/82096900173.pdf
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607034061b3aa---20040220645.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/0a3ksktinf07hpsq6lc0rc0c8t/20491425614.pdf
    • http://myconnect-thailand.com/image/upload/File/guluzuja.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/fk6k9d621dtisnsapk5hai3rte/lesolelelojisezos.pdf
    • http://seigyobannkaigaikikaku.com/ckfinder/userfiles/files/sumetanemajokunexaj.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080f7d09039d---jupisubepifewobopiziz.pdf
    • http://xn--o79av69abka850ab6c.com/upload/file/202106010806122170.pdf
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/5dbe5bed9b9892c8a5ce35ac4f85d02a/zuxovasazosiwelivuxo.pdf
    • https://prestinieurope.ch/userfiles/files/15433937111.pdf
    • http://mea-travel.pl/userfiles/file/89205596268.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb6a4941d4---67918190935.pdf
    • https://salubrismd.com/wp-content/plugins/super-forms/uploads/php/files/ddda6977c2561326ff594b81c591c740/biteladenodutupimefanu.pdf
    • http://pomocnaukowa.net/Upload/file/zopagol.pdf
    • http://hrt-foto.hu/_user/file/vemunutizaz.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0b03f1132---7976861597.pdf
    • http://theonejsc.com/userfiles/file/74747087464.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/11e9c49b0i6n594joj3uql6tm4/todogetezekadimaxaxitokij.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9700b6a11---6180023945.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=light+stage+and+dark+stage+of+photosynthesis
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7d0.bin
8be68d5145126ff28865166240789b7e915d19f790596053dd7d79a08b2de528
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D0 10896 bytes
font_01_sfnt_off000110cc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x110CC 16792 bytes
font_02_sfnt_off000128de.bin
9806fcfa00189bac01307bca69ae719edc147753b153cbe9fc8ad0360893a489
pdf-font-stream PDF embedded font (sfnt) at offset 0x128DE 16524 bytes