Malicious PDF — malware analysis report

Static analysis result for SHA-256 41aa0e23cc02648f…

MALICIOUS

PDF

83.0 KB Created: 2021-09-02 13:07:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: fdf7ab27d23ba0bb60f78d2f77d934a2 SHA-1: 892fb8febe7da3d0ee0cbf6d9e95aade605bf7a4 SHA-256: 41aa0e23cc02648f7e94277bdf15b2cf71aaab4e5133aa0bcf84f4b0725ac039
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm pointing to compromised WordPress uploads and disposable hosting. The embedded URLs, such as 'https://inwebjor.ru/uplcv?utm_term=ring+alarm+setup+manual', suggest a phishing or malware distribution lure. No scripts were extracted, but the PDF structure and URL patterns are consistent with a phishing or downloader campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://inwebjor.ru/uplcv?utm_term=ring+alarm+setup+manual PDF link annotation
    • http://moscowprice.com/content/xuploadimages/file/beron.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/zowedupig.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/2f753276569d1bae265cef8bacc00280/kukusol.pdfIn PDF document text
    • http://aristosaigonhotel.vn/uploads/files/diletarutesu.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b53cb338920---vomofojen.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/37fdurem6f21ot6ogas3nmh1s5/97887093781.pdfIn PDF document text
    • http://arabic.cz/ckfinder/userfiles/files/pemiwolegef.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085366922a18---sevutadukon.pdfIn PDF document text
    • http://elcolono.net/userfiles/files/2589972755.pdfIn PDF document text
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/vegon.pdfIn PDF document text
    • http://photou.cc/ckfinder/userfiles/files/49099126345.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/f9cd05d8ea95af49f67aee0a0759e784/mulexon.pdfIn PDF document text
    • http://abwlanham.com/uploads/files/vofelikotawajat.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b54b8880054---juxuvin.pdfIn PDF document text
    • http://www.taylormadetc.com/siteadmin/ckfinder/userfiles/files/83431553278.pdfIn PDF document text
    • https://madopin.com/calisma2/files/uploads/27755035051.pdfIn PDF document text
    • http://fluellentrees.com/clients/58222/File/gakim.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/86482365896.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/lowagobesa.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160939f65546f4---relifetolebotujikofalu.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_off0000dc04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF416 19668 bytes
SHA-256: 5e1e56e172af7a0c0670684816b18c17a71bf36ee15dded5c88b91372d787819
font_02_sfnt_off0001267f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1267F 10620 bytes
SHA-256: 77a3c8cdc8815ff90dfbd3cf357aa79cc4a1271985a4a34df2055745cc276686