Malicious PDF — malware analysis report

Static analysis result for SHA-256 f73dbac112f06370…

MALICIOUS

PDF

84.6 KB Created: 2021-09-23 12:09:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ffc78087639a752925e15080ccceb9c1 SHA-1: 4c96991f2d42c8fe7d8c13b10fb87e978980610d SHA-256: f73dbac112f063703551b374b86afb2ae3a53ffb8c6fb0dcdeee98a484ec5ac1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicative of a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://inwebjor.ru/uplcv?utm_term=trench+warfare+1917+mod+apk
    • http://phelieuviethung.vn/upload/files/45321354218.pdf
    • https://ismet.com.br/ckfinder/userfiles/files/24769360640.pdf
    • http://marmaraisg.com/images_upload/files/68472571919.pdf
    • https://matratva.in/userfiles/file/tabakumurenulaso.pdf
    • http://rabwork.com/media/file/20980552713.pdf
    • http://boonfagrandhome.com/user_img/files/pezakosujiparedetunem.pdf
    • http://karcannakliyat.com/userfiles/file/lanepezisapetozavevunifa.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148897d80fc2---rugumeziwigulapuraduwaber.pdf
    • https://magicdiscoradio.hu/userfiles/file/89421959885.pdf
    • http://zeroseistudio.eu/userfiles/files/jobekirukozawirad.pdf
    • http://birnagarcollege.in/userfiles/file/82261584464.pdf
    • http://coimbrasoftware.hu/images/uploads/files/nofarekorubinol.pdf
    • http://tw-tms.com/uploadpic/xw/files/vejigixufido.pdf
    • https://hkki.org/userfiles/files/16239379915.pdf
    • http://keifo.ru/ckfinder/userfiles/files/nisagaxevefagatutuxepi.pdf
    • https://chameleoncoupons.com/adgprocessing/uploads/files/35803426026.pdf
    • http://hongdacable.com/d/files/tijodalamejajow.pdf
    • https://yourwebcenter.com/files/file/sufaxodozasikonejawiti.pdf
    • https://chmelo.hu/sites/default/files/file/12487963091.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/65942b2f6026a82eefa771bf6b2be537/23866500638.pdf
    • http://reklama-kemerovo.ru/files/files/38105669943.pdf
    • http://triple-a.co.th/ckfinder/userfiles/files/38002351461.pdf
    • https://xn--49st2et51duvk.com/upload/files/10904119634.pdf
    • http://hokkaido-love87.com/app/webroot/js/ckfinder/userfiles/files/fidemafulojo.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614395d5b5cf1---kafokowetuloxafe.pdf
    • 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_off0000e4fc.bin
967de2596ad1cc34a22bb7396ba99670741d1fc9ec4cd639b7f4adbbd989b735
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FC 18028 bytes
font_01_sfnt_off00011367.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11367 16792 bytes
font_02_sfnt_off00012b7e.bin
d69399aa2c28132f5033745cbbd72b6b6acf48a02ad74bf2a5e85235901f29ca
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B7E 10892 bytes