Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3529df21322d671…

MALICIOUS

PDF

75.6 KB Created: 2021-09-19 06:55:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d54ef9324d955a4ea3714c7fbbec45a7 SHA-1: a26f89301ebe15b047698018d74b3ac979579847 SHA-256: f3529df21322d671e84f30a63403727112070db8e341f0fc231515186a4c7814
156 Risk Score

Malware Insights

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

The PDF contains numerous links, with several pointing to compromised WordPress upload directories, indicating a tactic to host malicious files or redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://csmgh.net/pevron/www/img/file/87224306351.pdf In PDF document text
    • http://surestegc.org/documentos/file/58906316248.pdfIn PDF document text
    • http://phatnang.com/media/ftp/file/xikabaf.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142629d79556---vofule.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee1f7bc05f---silutenap.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/saletodoxigekuvera.pdfIn PDF document text
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/bijegirumuxewejamu.pdfIn PDF document text
    • https://topconta.ro/userfiles/file/saletib.pdfIn PDF document text
    • http://hamlineparkplaza.com/assets/amund/ckfinder/userfiles/files/piwadapopulafiza.pdfIn PDF document text
    • https://bold-iot.com/uploads/files/202109020614378025.pdfIn PDF document text
    • https://loppisidjupdalen.se/images/uploaded/file/vibojikewofikagewu.pdfIn PDF document text
    • https://kawanmto.net/contents/files/90741378206.pdfIn PDF document text
    • http://nasledie-sluck.by/var/upload/file/revipozon.pdfIn PDF document text
    • http://hotelbellevuepalermo.com/userfiles/files/22916616661.pdfIn PDF document text
    • http://targhevaticane.it/userfiles/files/nunujekofetajukibavi.pdfIn PDF document text
    • http://digitalpolicycouncil.com/imagenes/file/53733400769.pdfIn PDF document text
    • https://somogyplusz.hu/files/gumadamisowigu.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/46672353382.pdfIn PDF document text
    • http://pcccmiennam.com/media/ftp/file/76565707707.pdfIn PDF document text
    • https://nocrime.cntwn.org/ckfinder/userfiles/files/futuwujoju.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/161339d2edbda2---piramozider.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/94544053525.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/zusomopivob.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=developer+kit+for+androidPDF 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_off0000c558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC558 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6F 10484 bytes
SHA-256: 3a36880f2ea368663a316398f670c39b1e4587cf896f83861925a6e0a4e72813
font_02_sfnt_off0000f558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF558 16864 bytes
SHA-256: 72ce8265db4b595950c8ff7c19a8ae00b6ec4e2f62ab97af3c3d95b595769169