Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf41f44fe33041b2…

MALICIOUS

PDF

82.4 KB Created: 2021-09-23 07:30:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fdc84fa6275ce4bfa101bf458688410d SHA-1: aa48cdb41e36a86fed6d789723725a1c257b6221 SHA-256: bf41f44fe33041b215da16a200c830a48e2cacd8f50726eeb15edd42277e0feb
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 WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 http://vidiniaibreketai.lt/userfiles/file/nepasuked.pdf In PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/jifax.pdfIn PDF document text
    • https://davnosti.ru/upload/60723232421.pdfIn PDF document text
    • http://huarui-bio.com/upload/files/31803721534.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16138ba6773cd7---gakutameraluxo.pdfIn PDF document text
    • http://cpghollywood.com/userfiles/files/vofoloz.pdfIn PDF document text
    • https://urology-andrology.com/userfiles/file/kamakuzexalet.pdfIn PDF document text
    • https://escolaalfa.com/userfiles/file/77085646265.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/41633775769.pdfIn PDF document text
    • https://lentes123.com/aym_image/files/waxog.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f696697e7d---34981090615.pdfIn PDF document text
    • https://bkairconditioner.cloud4demo.com/uploads/files/dubovojuwosenan.pdfIn PDF document text
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/60029521909.pdfIn PDF document text
    • http://ozt.zielonetarasy-cieplice.pl/uploads/userfiles/files/84819932357.pdfIn PDF document text
    • https://happyfun.tw/uploads/files/202109161255387884.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/6cc5da467e99f8dbd7701137750d93d1/27029081616.pdfIn PDF document text
    • http://sushinamu.com/uploads/files/8753665258.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/gotuvaw.pdfIn PDF document text
    • https://cmottaviproductive.it/uploads/file/90112882580.pdfIn PDF document text
    • http://almawred-sy.com/files/adminfiles/files/39236421355.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/baxejubukadexesokeru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=dhoom+2+full+movie+onlinePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dfc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D5 17628 bytes
SHA-256: 095848603fd2be23c3595dfcad3510b769628b972e8746f4c0f815aeda2c3f82
font_02_sfnt_off000125cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CB 10240 bytes
SHA-256: 3b1674f9b9fc5ac0178380a11e6f35d76ba6db527f0917cb4b7bacd1af0a1f27