Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5dc02fef5eb7e98…

MALICIOUS

PDF

74.8 KB Created: 2021-09-08 05:18:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b9052667b24064ec741f460af14080be SHA-1: 05e21fce4926d9868d54727c86c8d95c932a7d8e SHA-256: a5dc02fef5eb7e980c73d09563db1e12dcdd8d919e8159fac960c5712e81b8a3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure itself likely contains embedded links or JavaScript to redirect users to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://medvor.ru/uplcv?utm_term=dunlop+cry+baby+wah+manual PDF link annotation
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/9a7406c6ebcde42c628c2235e02a473b/40585009793.pdfIn PDF document text
    • https://alpinismbihor.ro/app/webroot/files/userfiles/files/buvogekefipetagu.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/suvoto.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606ddc1d5629d---favedejivax.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160779d420501a---fujanubemuvukuje.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/fehlig42arti7ir99gmdk30824/83145790581.pdfIn PDF document text
    • http://weilandensemble.nl/ckfinder/userfiles/files/zogoxu.pdfIn PDF document text
    • http://casaalu.com/luutru/files/53361626291.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/bulesuromanamutiwubipuvi.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610d78d728aac---xefato.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611f8e67b2272---kosobelaz.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc549a8b3b---28940865746.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/41b9b053a02dd0987be651ffb97ebf96/dozevikatujijilugodeguz.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/k08fsobvc6bo6nu14m9p92f2r6/woresufepefamamola.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160872b6acd37f---96719986054.pdfIn PDF document text
    • http://speednewslive24.com/assets/ckfinder/core/connector/php/uploads/files/73168711326.pdfIn PDF document text
    • http://short-story.ru/upload/file/mudadutuwusago.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/doxojinupozef.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/ad10547793e35b751c4550e546ce2355/tuxiwagopapikuvazewizifi.pdfIn PDF document text
    • http://guowangcable.com/d/files/maneziromaravikomugunem.pdfIn PDF document text
    • http://tantex.org/tantex/tantexuserfiles/file/36057556180.pdfIn PDF document text
    • http://cutskytools.com/d/files/wesosuwabanabunus.pdfIn PDF document text
    • http://myarrahnu.com/mo_images/files/36719778427.pdfIn PDF document text
    • http://liga-stf.ru/i/upload/files/25737510552.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_off0000bf03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF03 17380 bytes
SHA-256: 30775c3b91964e25192318aab8cee6d841a24b9c0dce2483380db681922bc306
font_01_sfnt_off0000ec58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001046f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1046F 10592 bytes
SHA-256: 6bec1753443a51d67d89357e4abd422f17784d6639f6829a086f7ae05887f9fd