Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5a1c9918d1a2747…

MALICIOUS

PDF

83.9 KB Created: 2021-09-06 08:24:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 641cc6615732635a5af2bdd4d2848588 SHA-1: c109cfa3dbb67185e063ed861c71134b6d388672 SHA-256: c5a1c9918d1a2747738b3bb75e33ed9826c0ff90a69b3cd7dc0d56b8fd89db31
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised CMS upload directories or disposable hosting domains. This structure is indicative of a link farm designed to distribute malicious content or phish for credentials. ClamAV detection and ML classification further support its malicious nature, suggesting it's a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://fmafirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/38324636272.pdf In PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b06f9b6489e---17772588212.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/82697371288.pdfIn PDF document text
    • http://ruihuitax.com/files/file/firafikawarijekezafinereb.pdfIn PDF document text
    • http://bangdientunhk.com/upload/files/vojew.pdfIn PDF document text
    • http://edmo-cars.nl/images/file/21279120370.pdfIn PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/mvjr6lla76gnreibe4fsj3kdd7/64280617140.pdfIn PDF document text
    • https://dotcomtravelegypt.com/userfiles/files/zawitaboxozame.pdfIn PDF document text
    • http://thrifty-uy.com/files/others/wubefokunurodazu.pdfIn PDF document text
    • https://garraldaarquitectura.com/garralda_userfiles/files/48640052227.pdfIn PDF document text
    • http://goodwynva.com/clients/d/de/de91e19d235d8a3764238851c6b73f99/File/6251415500.pdfIn PDF document text
    • https://atraba-holding.com/userfiles/file/74800412442.pdfIn PDF document text
    • http://sibinetweek.ru/userfiles/file/94659569988.pdfIn PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/nenatej.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/79132836638.pdfIn PDF document text
    • http://www.lugashotel.com/data/editorfile/50706681630.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/2045e8bfdd97270e0c684170c42fb09b/592033766.pdfIn PDF document text
    • https://webmenuplus.com/images/file/xabufapisunabafanumis.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5725ecea8---kogifatufimevorilakavi.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/710db99c5a11d38e9649aa907d24cd4c/30919490076.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16108df846c091---pekudisuzalezuluvasa.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/7c57e8c7330fbefcf5352f5f8bcb5e58/zowikoxasesiromijaxoke.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090ec020b3ea---xevitobitiziginuka.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/sotin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=io-360-c1c6+parts+manualPDF 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_off0000e05e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05E 10908 bytes
SHA-256: 0150cbec91ad5118f0059f7f55e47c43ec6a49ba38468636458960165c22ba14
font_01_sfnt_off0000f9bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000111ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111CE 18704 bytes
SHA-256: e89735ebf36395428a428852eba707794baa36c296d0d55e0feeeefe10cb0c56