Malicious PDF — malware analysis report

Static analysis result for SHA-256 57829ccf1b4ba3c8…

MALICIOUS

PDF

81.7 KB Created: 2021-09-13 21:31:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5138562841ebb926c7f8ea0a199c40fc SHA-1: 9b51b31be426fadd2c8671fee7a2c186993c72af SHA-256: 57829ccf1b4ba3c85d52076bc06b9f457717557fd4bbfa1ad7f253c0e21ccf81
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to external websites, many of which are hosted on disposable or compromised domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://trexanh.net/upload/files/bisapofebe.pdf
    • https://juniorclublivorno.com/sitonews/images_upload/files/kujikil.pdf
    • http://jingyilin.org/uploads/file/babuxonuxuwubipux.pdf
    • https://plasy.com/uploads/file/rudobokowimo.pdf
    • https://gloriamus.org/Uploads/userfiles/files/kovegezaginibarereseki.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161377c048dc77---12159476000.pdf
    • https://stpeterscbs.ca/ckfinder/userfiles/files/lijekukopezonufe.pdf
    • http://medicom.pl/userfiles/file/laluzitovetamafoz.pdf
    • http://jj-metals.com/userfiles/file/2021090913565873499.pdf
    • https://trimix.bg/UserFiles/File/81650125209.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c138c78cee---56065406190.pdf
    • https://infotechsystemsonline.com/ital/www/img/file/kejuzufomabudusonivugu.pdf
    • http://duocmyphamcongty.com/app/webroot/uploads/files/10918283373.pdf
    • https://bonekarusa.com/contents/files/lafibexoxa.pdf
    • http://langeline.com/ckeditor/upload/files/rivowetuwi.pdf
    • http://hytechcommunications.com/userfiles/file/zedukimumajuguvezebiwud.pdf
    • https://aldaserwis.pl/ckfinder/userfiles/files/movusedizivodami.pdf
    • http://lamelove-zakryti.cz/userfiles/file/82921516367.pdf
    • http://alexandersorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/68830950091.pdf
    • http://tokstar.com/_UploadFile/Images/file/walefevepazafepekepo.pdf
    • https://libertyrealestate.in/ckfinder/userfiles/files/lifeguvoginozapesomabo.pdf
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/40752033cf10c6706f4ac2e6a7d68c29/gesewolob.pdf
    • http://gnatowski.pl/attachments/file/5796496987.pdf
    • http://mjengo.org/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/dobonuvifisekezifino.pdf
    • https://arhometutor.com/userfiles/file/bakinefidesiforoduwu.pdf
    • http://ecohost.ru/pics/images/file/legerapepisifa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=iphone+download+not+working
    • 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_off0000daf3.bin
2c6de37ad8a68086d0e67eb2bfa8d8fd740afd9e87cf4726457b83f755a75929
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF3 17900 bytes
font_01_sfnt_off000108bd.bin
cfb699b42895dab47b32ce83d7a1a825b50f46f868224a819c68139716d51ae2
pdf-font-stream PDF embedded font (sfnt) at offset 0x108BD 10632 bytes
font_02_sfnt_off000120d1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x120D1 16792 bytes