Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9be1d7270c6f1e1…

MALICIOUS

PDF

71.9 KB Created: 2021-09-13 15:06:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f4a977c436fba0ef24291bd7d1f8725a SHA-1: afd6b0d5edad2080a415cf6bb2af6737c10b998f SHA-256: a9be1d7270c6f1e12d5c69b8db31df5cc77cd6970da86158dcc82fc689ee351b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, indicative of a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farms points towards an attempt to lure users to malicious sites.

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://ketchas.ru/uplcv?utm_term=do+not+disturb+auto+reply+android PDF link annotation
    • http://rsentco.com/upload/file/nuperibolufog.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/e56e4daf6f6b48411e843838b9ba880a/bufijito.pdfIn PDF document text
    • http://gurukripapublicschool.org/userfiles/file/lawago.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/1916685311.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/63182494632.pdfIn PDF document text
    • https://www.xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/rekoj.pdfIn PDF document text
    • http://likuidart.com/files/ckeditor/files/45311928304.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/272af9rigf0c2sq5heq11lkkm0/34843193750.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/papozisetajone.pdfIn PDF document text
    • http://thebodyclubonline.com/userfiles/file/jetolokibofema.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/fobofisirofu.pdfIn PDF document text
    • https://plentis.eu/ckfinder/userfiles/files/judew.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/jesofegekofitapigimi.pdfIn PDF document text
    • http://snbedu.com/uploadfile/file///2021090110535976.pdfIn PDF document text
    • https://s-oil.hoakhanh.vn/uploads/image/files/miburax.pdfIn PDF document text
    • https://posetili.ru/userfiles/file/pekejotomosi.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/vagudabofikewugonewaluniw.pdfIn PDF document text
    • http://ahnil.com/userData/board/file/zajonepatosatabuxamep.pdfIn PDF document text
    • http://www.centrosanmarco.eu/img/news/files/pixokogugutezuw.pdfIn PDF document text
    • https://sunarchegypt.com/userfiles/file/58580055694.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad73adf32e---89987712379.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/boroxok.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/3450455108.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/87962922240.pdfIn PDF document text
    • 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_off0000b80c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB80C 16108 bytes
SHA-256: 9a096a806cc5aa13dd733bf46748f659bccee448a78c217f0c095ae45b351b84
font_01_sfnt_off0000e11d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11D 10740 bytes
SHA-256: 1ef4cafb476db1eb675107df328acbed238019abe98d4b530f79b0751b53b122
font_02_sfnt_off0000f9bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1