Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d242684d52fd8f9…

MALICIOUS

PDF

70.0 KB Created: 2021-09-20 00:05:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a7f5d1097a021dd9b7b42f6380f552d SHA-1: 7f8f5863159b8179c7a4b85e898598e265e3b530 SHA-256: 7d242684d52fd8f91bcd57067f9579df75f773676c5f0a641fa97f7384bacd0b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV specifically identifying it as Pdf.Phishing.Trojan. The presence of numerous external URIs, many pointing to compromised CMS uploads or disposable hosting, indicates a link farm designed to redirect users. The document body is heavily obfuscated, suggesting an attempt to hide its true purpose, but the overall structure and URL patterns strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://archism.ru/uplcv?utm_term=gun+strike+mod+apk
    • http://rubivina.com/Images_upload/files/notezafisudotifosevil.pdf
    • http://youzedu.com/ckimages/files/20210901155516344802.pdf
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/10887583719.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/00303c153c9412d4a6395307a0052af7/mowubopuxamivup.pdf
    • http://yuanjen.com/ckfinder/userfiles/files/36553188955.pdf
    • http://psychanalyste-gard.fr/ckfinder/userfiles/files/ririturawizoberowaveza.pdf
    • https://foundationkuzmanov.com/files/673299040.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/46687579034.pdf
    • https://alley.52886.tw/uploads/files/jigig.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16143207ac9991---noladi.pdf
    • https://generalaudit.pl/eurostyl/photos/file/38339491132.pdf
    • http://avistravel.ro/userfiles/file/jazezijumovejifog.pdf
    • https://ibrahimkoc.com/images/Media/files/77547145391.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139921aafdcd---58947523224.pdf
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/2c6mb3abgh917tideksft23rgo/lajuwafifugajeno.pdf
    • http://bisenzia.it/userfiles/files/nunan.pdf
    • https://franchiseharbor.com/files/files/kamezexokopuvufalawe.pdf
    • https://penal-garazh.ru/files/5126554918.pdf
    • http://zjgjqmr.com/v15/Upload/file/202192050568848.pdf
    • https://sikanderajam.com/Robinson/ckfinder/userfiles/files/11278420461.pdf
    • http://yamamatoen-wanwan.jp/ckfinder/userfiles/files/95025438851.pdf
    • http://woori-tour.kr/FileData/ckfinder/files/20210915_9399941522C3C01F.pdf
    • https://sailstudy.in/ckfinder/userfiles/files/86336956357.pdf
    • https://oceanflowerhotel.com/uploads/image/files/98451467064.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_off0000b4a6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4A6 16792 bytes
font_01_sfnt_off0000ccb8.bin
d29efb79b88ca8fcfdbaebd202ba7f5568cb677d28202daaf7caa835544b88ba
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCB8 14784 bytes
font_02_sfnt_off0000f1b8.bin
e416d8f0ea0ed5c555d13a7d9bef5c37092db311622e623314d44dc61a18997c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B8 10740 bytes