Malicious PDF — malware analysis report

Static analysis result for SHA-256 993faa39872a9154…

MALICIOUS

PDF

104.5 KB Created: 2021-09-06 23:54:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 153d91afd8a683ef17206bdfdb246efe SHA-1: a8ba4035e9d460876592f727316837fafc8a72da SHA-256: 993faa39872a91542333d0ac54daa76ea662f5efa4ac2fec0f8c5dbd34200432
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. These links likely serve as lures for phishing or to download further malicious payloads, aligning with the characteristics of a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crewmak.ru/uplcv?utm_term=original+aryabhatiya+pdf+download PDF link annotation
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/e72a36493232c2bdfc01c6d642b961f4/nevawajamimutawug.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/48085254088.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/5fe781b9016922f79a985314138fd2a6/44539953721.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/fawufiketipefax.pdfIn PDF document text
    • http://clarasonic.com/upload/file/54740953090.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/sijejonosamuwuwete.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/16096672a19c32---97756049284.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/b2f627d96c7d0864a3328e4d1bb35068/dekowiravug.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/a4f00fa59a2d11e5f93f7f2342b7a5a3/soloderikora.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160854b0edc110---naludofavubogopotikumom.pdfIn PDF document text
    • http://camberwelltaxi.com/survey/userfiles/files/13304849529.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/160caa5dbf35df---bujomabajawoboxogeresi.pdfIn PDF document text
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/deviterisejutajorewanesat.pdfIn PDF document text
    • https://daotaolaixesontay.com/uploads/file/71291788004.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/cv4ojiko0c4ep0n9a0ie8cgcfp/48731236704.pdfIn PDF document text
    • http://antoniolescio.net/userfiles/files/bujivonurunuwoxa.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/18688941819.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/be996ppl70nj48qtjcai7b46l8/fasiposatetanigigef.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/7da34t52s5re492vn17dek83a4/zomij.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160c8993a3d4a1---powakusaxatamese.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/a3gl776ml0prirk5db83q31gl5/wesila.pdfIn PDF document text
    • http://thucphamchucnangmy.vn/uploads/files/45121145066.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_off00012c6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C6D 21008 bytes
SHA-256: acee530021ab95406c36cd4a2e034b6823c0100aa99e0cbe42d45e770b7777d1
font_01_sfnt_off000163bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x163BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00017bd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17BD6 10844 bytes
SHA-256: 2bd45385290eb525841507ee8199b6458b3124f8df1abdfbe37ccd041d9d674c