Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d731429f7a874ef…

MALICIOUS

PDF

83.7 KB Created: 2021-07-02 01:59:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 68f9f42e9d6ee77f581f5d5caf75bc39 SHA-1: 7ce6a966f70f6c85c59cb076b4d8bf057ab6519e SHA-256: 8d731429f7a874effa19554436c13702ac79f1d55273b9bdbceec7d15bf3ea3e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to disposable hosting and compromised WordPress sites, suggesting a link farm designed to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://archism.ru/uplcv?utm_term=ncert+science+book+class+8+chapter+16+solutions PDF link annotation
    • http://babamoleskine.com/files/file/sigowavasenozuwevopazunug.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/57796707203.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/wutodovivewuv.pdfIn PDF document text
    • http://mppscstudy.com/admin/usercontent/file/tovisusuk.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/gozukup.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609f1c5d0ba5e---pezadezivamojulikur.pdfIn PDF document text
    • http://vejwun.cz/images/7413048380.pdfIn PDF document text
    • https://klairtransport.com/uploads/files/nodavujoj.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/3k5v1o3cjdf48ac6sg1gte93bf/96859584518.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/829t51625ob2r8nejdscembm8a/97676870272.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202106file/2021061008433770554.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c8cb01594eb---34215710674.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/1552b101a025525047772ed43657f8b1/26196297121.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/52631567162.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/79483223755.pdfIn PDF document text
    • https://belhasasecurity.com/userfiles/file/34918100672.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/e2md2eh3ovkvq3pq3nonelv86r/kewezinojavijar.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bec8bc52d64---9355973624.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be8248b0aa0---vudibetalorezupuzolabosol.pdfIn PDF document text
    • https://banderlogclub.ru/Files/file/jetaseso.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e31e0746d---vetetadeledaxidedapaved.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f0e6c400c---88780358907.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/64828877790.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/53356994101.pdfIn PDF document text
    • http://evola.it/userfiles/files/kigibivoxibarit.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_off0000e3f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3F6 16612 bytes
SHA-256: ac92deefbf44716ae9b6e71eb188f0d7ea8f1aa67af86935b14068d9ac2ab664
font_01_sfnt_off00010f22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012739.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12739 11208 bytes
SHA-256: f88f5815a7b5a74f98eefcd54f133c25a1e23b7edb931a4a50e8dee4824e5c41