Malicious PDF — malware analysis report

Static analysis result for SHA-256 21a2bfdaf3eb61aa…

MALICIOUS

PDF

87.5 KB Created: 2021-07-15 13:19:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e7d5c1ae8f22edae4254603170b5faed SHA-1: 3d7aca1cff771e32a1e3980dc5f61ffb1d6c7998 SHA-256: 21a2bfdaf3eb61aa5954a5ea4656484dc9bc37f3897642879d6974cb6e273c3c
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs, many pointing to compromised WordPress sites, suggesting it's designed to lead users to malicious content. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a large number of links on disposable hosting, further supporting its role as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://bmcnx.com/userfiles/file/durevolerileputoja.pdf
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085c99379147---50035125758.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/n1sne86q5t94if42hct4t7npos/sewibetovejebume.pdf
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/bv0ibhkk2doke22i4r856qt3g3/tidirubusas.pdf
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/506b84247ace258a9db69344b4bbeebb/74701961089.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609545b6a77c8---lerevudosefuxematoxore.pdf
    • http://aucoindeshalles.com/menu/file/84021037587.pdf
    • https://bruceautoservice.com/files/file/serepolilodusa.pdf
    • https://angelsforwarriors.org/userfiles/files/pipefiligozobuwixeruwu.pdf
    • https://www.utn.ac.cr//sites/default/files/files/20066068304.pdf
    • https://ayurvedaemart.com/uploads/file/14621840397.pdf
    • https://www.surajinformatics.com/wp-content/plugins/super-forms/uploads/php/files/9ef29726323c19e507592892325e920b/luxitaxog.pdf
    • http://kondicionery-vidnoe.ru/upload_picture/file/46993873985.pdf
    • http://habitat3.eu/userfiles/files/jazujavuviji.pdf
    • http://eprdel.cz/userfiles/file/86296523755.pdf
    • http://kaowei.tw/image/files/20210605_090356.pdf
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/mpl8ra1cejacda1nj2j741fp57/gatipupi.pdf
    • http://shsuorui.com/uploadfiles/fckeditor/20210625/file/16246458352193.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16094360d54db6---gefilolufaroxateginiw.pdf
    • https://khonggiansachhanoi.vn/uploads/files/bunuwotuwiro.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f241716c9b---xakorus.pdf
    • https://ryokanclub.com/FileData/ckfinder/files/20210705_CBD2AA93B3EC29BC.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608d4935df0a3---58130401333.pdf
    • http://animationcoach.com/userfiles/file/39430630304.pdf
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/sdauavtmo9loo921vrg2us0nv2/damijovigufojulezeliv.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c511668e4d2---luzanewaboleramarib.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=positive+l+words+to+describe+a+person
    • 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_off0000f0de.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DE 16792 bytes
font_01_sfnt_off000108f5.bin
d393cab9642e9df94b1769d1e5bbaaebde791f37b0cefd5ae0069a004250db04
pdf-font-stream PDF embedded font (sfnt) at offset 0x108F5 10800 bytes
font_02_sfnt_off000121d0.bin
8104f4f39c2b379e225037017347242d9a44a7ae5d3ae7dc2a05ba1d7a6370d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x121D0 17636 bytes