Malicious PDF — malware analysis report

Static analysis result for SHA-256 383c8922c1e98f0f…

MALICIOUS

PDF

69.2 KB Created: 2021-09-07 11:33:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 8429b10f4ed2601ef66b6e1fadc77678 SHA-1: b8ddaaaffb41c9cbfdc66de6aaedfc7dbf047b6b SHA-256: 383c8922c1e98f0f8c25247804e9d5e279ac6391d1604ea89047b7b83242267e
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress upload directories, suggesting it functions as a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure and numerous external links align with techniques used to obscure malicious content and redirect users to attacker-controlled sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://nesemlak.com/test/images/uploads/files/kufisewixiluboreki.pdf In PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/300b36e55f705470e7160dfa8e13f28d/nudate.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/8b7dedacef420ba4ed3c20458e54e8df/lilajoxeludasum.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/7677925525.pdfIn PDF document text
    • https://sieuthimayphat.com/ckfinder/userfiles/files/xufig.pdfIn PDF document text
    • https://henklinders.nl/henklinders/upload/files/17666677588.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/67739302068.pdfIn PDF document text
    • http://ladakhtripmaker.com/userfiles/files/33313667457.pdfIn PDF document text
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb7cb60435---gosabilevizejorawo.pdfIn PDF document text
    • http://klimagra.pl/images/wysiwyg_img/file/53388174096.pdfIn PDF document text
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/4lf9b16s7409lu58df7tuut2ui/16515288794.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a79034d7851---2130445813.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/qscj3do99bjm5hkug9ph0aq6kd/65821187446.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/winamazorutudepe.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/65672456.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/samulutojesikidev.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/wozivil.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099cb8aa7981---51069211679.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4589acef3d---99031436427.pdfIn PDF document text
    • https://cfi-registration.org/buzzboxgift/img/userfiles/files/tanomojukodikoke.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607495e180f27---sewatufapadoxok.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081e4be829b2---72630720058.pdfIn PDF document text
    • http://zjhywt.com/images/upload/File/74842364908.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a1f918fab---75437779642.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=estireno+acrilonitrilo+pdfPDF 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_off0000b205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB205 14764 bytes
SHA-256: e80072292e85638cfc83b9facfb9c434305829278a3b272cb4308acd0644b96e
font_01_sfnt_off0000d730.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD730 10596 bytes
SHA-256: a0d94997296768d0bbb1c6c819131ef921082f4b436349606998b3deef4c03a9
font_02_sfnt_off0000ef83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1