Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b11f3b3af2b841d…

MALICIOUS

PDF

72.9 KB Created: 2021-09-24 18:01:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8f9a0585ef6417ca97852c9cd5248939 SHA-1: 55b677ad7829c501819245927a8cd1c57c899749 SHA-256: 9b11f3b3af2b841d447efbdb4d5e05eb097ba4b8f099732e1c578248f7506633
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, and it contains embedded JavaScript. The heuristics indicate the PDF acts as a link farm, directing users to external URLs hosted on potentially compromised or disposable domains. These URLs likely serve as downloaders for further malicious payloads, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://wastran.ru/uplcv?utm_term=recover+formatted+phone
    • https://readandenjoy.ae/userfiles/files/sajumetabul.pdf
    • http://boonfagrandhome.com/user_img/files/85777433777.pdf
    • https://qwert5.com/psum/admin/userfiles/file/foxig.pdf
    • http://ettorebelfioreliutaio.it/userfiles/files/10222985395.pdf
    • https://penzehir.com/dorceiys/ckfinder/userfiles/files/rukurivatopogudotab.pdf
    • http://songhandiban.com/uploadfile/file/2021091415365173499.pdf
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/mumawopewivazajosabuvunob.pdf
    • https://ferdavagnar.is/images/fck/file/satutatolele.pdf
    • http://intertexmedical.com/userfiles/files/xuxigal.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614199da6a41f---77981202736.pdf
    • http://itkaufmann.com/images/fckimages/file/vavesawaxazo.pdf
    • http://sunil.kr/uploadfile/fckeditor/file/88565035900.pdf
    • http://gamax-motor.cz/data/dokumenty/41108722237.pdf
    • https://kga-am-adlergestell-ev.de/kga/ckfinder/userfiles/files/lanidufelugugoz.pdf
    • http://badaranquehablar.com/userfiles/files/21358527871.pdf
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614578768a200---80929030894.pdf
    • http://babyindex.nl/images/uploads/82721652293.pdf
    • http://www.portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/juzofirivurujezugedop.pdf
    • http://3t-t.com/User_File/UpFile/file/20210920094500_em9kZXZhbWU=.pdf
    • https://rafaela-motores.com/userfiles/file/68350305940.pdf
    • http://ntvietnga.com/upload/files/legedipuzesibo.pdf
    • http://sbstroy53.ru/img/files/81959340680.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2c9a5c4da833993e0449598261f19ef1/runibujomo.pdf
    • https://tselectromechanical.com/uploads/CKfiles/files/21985166505.pdf
    • https://indirimlipin.com/calisma2/files/uploads/sikojojosupubugazirigogu.pdf
    • http://veszpremlizards.hu/_user/file/91560046620.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_off0000b565.bin
58c64e7875714d7fd0b90296cab13e5e52ea7a8ca78c3f75942515c4d822a284
pdf-font-stream PDF embedded font (sfnt) at offset 0xB565 10692 bytes
font_01_sfnt_off0000cdbe.bin
d75b427f0593fef6d524a6152a4459d539e3403bd0210af57971c6fff8dc1dd2
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDBE 18692 bytes
font_02_sfnt_off0000fe5d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE5D 16792 bytes