Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdcf6466d2e48488…

MALICIOUS

PDF

86.6 KB Created: 2021-08-19 01:36:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6c7439668915d1f251441c4cd9d9d0bb SHA-1: 4ee67bd8907a99208f40d3a6b95923e6b74cc214 SHA-256: cdcf6466d2e48488b1cc175cf5b25ad4a45f20976f4f9e892e899f36ec8b2962
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. Heuristics indicate this is a link farm on disposable hosting, and ClamAV detected it as a phishing trojan. The ML classifier also strongly flagged this PDF as malicious. The primary function appears to be directing users to potentially malicious or phishing content hosted on compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://consulcongress.it/uploads/assets/file/jituf.pdf
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/mnbbeq2d0he4qh0ireb7flajq5/tegipilipasupojutonada.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/720bedbb98138dc41a585e0f1dda5049/zuruxuvixuxalubanoxufel.pdf
    • http://nuovojob.com/userfiles/files/mufixunivijotojabuwuku.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a44b089404d---11357154710.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b72f5402508---93524052462.pdf
    • http://anhuifan.com/upload_fck/file/2021-5-2/20210502053845971186.pdf
    • https://fisheaglesafaris.net/pics/user/file/xojagewosij.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/8ar8h1dqg3ap2c4nm15h2saik9/97292038009.pdf
    • http://climtech.com/files/files/relosare.pdf
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/osjbqe29p89rf51p0e0knfmodp/35145158275.pdf
    • https://hunghiephuylog.com/upload/files/ninitivakufubikas.pdf
    • http://soepcentrale-dekeyser.be/userfiles/file/31483646532.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16075fa395d0be---mawowusekexe.pdf
    • http://jmdfhjl.com/fckeditor/userimages/file/50732967924.pdf
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/27744355100.pdf
    • http://huh.hu/UserFiles/File/vofazutoparebidepita.pdf
    • http://net-marketing.hu/images/files/pesipu.pdf
    • https://zifu-tech.com/app/webroot/userfiles/files/pokazulefadorenokebef.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160835a2b06a77---15605552257.pdf
    • http://jingluo.net/uploadfiles/files/9676562196.pdf
    • http://kielcenoca.pl/files/file/99550991625.pdf
    • http://tulsamemorialclass1969.com/clients/8/8b/8b8b36ecbaf17f244e47af75a29dfbe2/File/44305157857.pdf
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/9eaf96957726d8703218d22fa947f557/92361718706.pdf
    • https://alakharia.com/public_html/userfiles/file/rosane.pdf
    • https://fertilizerproductionprocess.com/d/files/puxilukoragilijunopiwav.pdf
    • http://jirehenl.com/userfiles/file/090400092886.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+many+calories+in+starbucks+iced+chai+tea+latte+with+almond+milk
    • 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_off0000e88e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE88E 16792 bytes
font_01_sfnt_off000100a0.bin
673329f9c4f598cc283763d475c9cb5d1b20342b48fe547dc76e9cec52661735
pdf-font-stream PDF embedded font (sfnt) at offset 0x100A0 18360 bytes
font_02_sfnt_off000130e3.bin
439bbc95b4cb76a3330f4941184cc3afc949c930b08b60e19a522aab087dda51
pdf-font-stream PDF embedded font (sfnt) at offset 0x130E3 11156 bytes