Malicious PDF — malware analysis report

Static analysis result for SHA-256 b73667e0ca88e4c6…

MALICIOUS

PDF

80.1 KB Created: 2021-09-07 10:12:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2b49e335670ec5a80694c4971da359fb SHA-1: 1783f054260fee920c7b7cd5a879dbd93f726b33 SHA-256: b73667e0ca88e4c6367919196eee8f7f85907ad7cf6c037816938dad18145125
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious PDF designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://coretry.ru/uplcv?utm_term=neurology+pdf+files PDF link annotation
    • http://sallytour.com/FileData/ckfinder/files/20210717_3A22DF5BFDA02DF1.pdfIn PDF document text
    • http://norrlandet.se/userfiles/file/82660569813.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099d2bc3c948---vagoziberawosemoduzijuxem.pdfIn PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dcb35d86e6---solepuroj.pdfIn PDF document text
    • https://olboihorgaszto.hu/editor_up2/85695024241.pdfIn PDF document text
    • https://altinhediyeler.com/calisma2/files/uploads/39852248991.pdfIn PDF document text
    • http://media-production.net/admin/ckfinder/userfiles/files/49754936171.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/11084083655.pdfIn PDF document text
    • http://stphilomenaonline.org/userfiles/file/lexuwedupovenegibi.pdfIn PDF document text
    • http://ap116.ru/userfiles/file/guvisiwu.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160820d0ab5aa2---balanikuku.pdfIn PDF document text
    • http://farashimirooz.com/files/10926475899.pdfIn PDF document text
    • http://regcureguide.com/files/files/lupaxororixuxogesazek.pdfIn PDF document text
    • http://sochi-vitrazhi.ru/ckfinder/userfiles/files/63902600264.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a78f70ba9d5---52006525433.pdfIn PDF document text
    • http://angeladaniel.eu/uploads/files/20006021220.pdfIn PDF document text
    • http://www.papelerialapiceros.es/ckfinder/userfiles/files/2079095725.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607265053cf61---26891006135.pdfIn PDF document text
    • http://dush-kz.ru/uploads/fck/file/sugake.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16100305403fb7---1596851581.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/fovafovudigif.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc9aac2e2a---56246774527.pdfIn PDF document text
    • https://areicon.com/images/file/fuvewiredovuwobokukulo.pdfIn PDF document text
    • https://bostaninsaat.com/image/files/24051777599.pdfIn PDF document text
    • http://doks-films.com/pcms/content/file/69683805295.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_off0000d79d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD79D 17052 bytes
SHA-256: beb88233b55879ee6d7ba72cc2b8a75bedc581435a0c91f989ab63ed65316849
font_01_sfnt_off00010390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10390 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ba7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BA7 10500 bytes
SHA-256: 0f870a33a7cdfbc9996ce9de465b452acc1c1c4392e72d78bb37921543d4b3c7