Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7e81b13b9f350a1…

MALICIOUS

PDF

91.7 KB Created: 2021-07-20 19:35:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 08f792d5a02c58939a0d225c1e08285d SHA-1: 7112b9b99f9b5c8d91a7a24209267d2313cc5703 SHA-256: a7e81b13b9f350a1a2acff50745a295f64dbe01ee430be5619ff507dac69ef66
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to compromised WordPress sites, acting as a link farm. Heuristics indicate these links are designed to lead users to malicious content, as confirmed by ClamAV and ML classifiers. The document body is unreadable, but the overall structure and URL analysis strongly suggest a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/c5196ce8a0ae991ed2c0b82787914938/83249519494.pdf In PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b698d8b68---gifavasowiped.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/jl7fflp7r08kqjn0o38qhcapqe/jodefamunak.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/gujilisufetejubefasapov.pdfIn PDF document text
    • https://laser123.com/geektic/files/74981428073.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/27c798f2dd6ebc58fa761a194821c809/zipoponetukobifage.pdfIn PDF document text
    • http://uppercanadatwocylinderclub.com/clients/877835/File/wukozopemupelijogufaxos.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/d8e16fb3ada6450e784d9f3854450fe9/96094839.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/jojuzafob.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b06216ea5db---dudunirewutawiremiti.pdfIn PDF document text
    • http://deforma.it/userfiles/files/xadubekakojejojokivevam.pdfIn PDF document text
    • http://dgjst.com/upfile/file/nijugagelurubirisibexe.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cffba90507---gifimizosamotomuguf.pdfIn PDF document text
    • https://etest.vn/app/webroot/uploads/files/72962682520.pdfIn PDF document text
    • http://fouladsazanco.com/Upload/file/79451771333.pdfIn PDF document text
    • https://nevisnews.com/userfiles/27333631150.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/wepamegabubupifatu.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/jutit.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/91264925799.pdfIn PDF document text
    • http://7tec.ru/userfiles/files/fasodafudojakozisanasu.pdfIn PDF document text
    • http://sorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/29855624326.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/7d2v0q2uqjci35ruupdqbracf5/silejeleserufimosoberewap.pdfIn PDF document text
    • http://fzcce.com/aimgs/uload/files/55940602772.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=the+rat+pack+movie+streamingPDF 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_off000100d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000118e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118E2 18036 bytes
SHA-256: 5ee3a170adc0fccdd921c14e1ab71a5ead8b69d9871ac70c2e3329be49a7b383
font_02_sfnt_off0001488d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1488D 10896 bytes
SHA-256: d8e8bac88ec3ceeec3fa7e51aa9591b51c66a80d6b5789a92918ad9b3b9f13fc