Malicious PDF — malware analysis report

Static analysis result for SHA-256 919db31e61a20ef8…

MALICIOUS

PDF

71.4 KB Created: 2021-09-12 12:18:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 49a1615be741843a93b6c97272da2193 SHA-1: cadf36ea0529b8b0ac12f4506f7aca8629281b2e SHA-256: 919db31e61a20ef8f817f899fbfde78b76e8f287fe95eed59dff6922f5a4a3bc
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs pointing to compromised websites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The `utm_term` parameter in one URL indicates a potential phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://allytemp.ru/uplcv?utm_term=bloons+td+6+hacked+unblocked PDF link annotation
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161300a4b54396---72083091096.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613760c36fff5---firoganofaboderekenok.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134319acc9fd---lilisezusovulaxeriragogo.pdfIn PDF document text
    • http://tokyo-sanritsu.com/userfiles/file/45633865348.pdfIn PDF document text
    • https://serihosting.com/calisma2/files/uploads/vifeleredupojex.pdfIn PDF document text
    • https://phnews.ro/files/file/12516345614.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/80420477585.pdfIn PDF document text
    • http://revize-elektro.info/UserFiles/File/16957442779.pdfIn PDF document text
    • https://intrastorg.com/userfiles/file/22629733418.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/93318262849.pdfIn PDF document text
    • http://emblem4home.com/UserFiles/Member/File/10414397997.pdfIn PDF document text
    • https://urbanshapes.in/userfiles/file/22628493177.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/76385323094.pdfIn PDF document text
    • https://bank-kredit.at/ckfinder/userfiles/files/natirikuweke.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/zetuxukodiguva.pdfIn PDF document text
    • http://artvideo74.ru/upfiles/files/wagezaxeduxerozu.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/nejitowanujofibadejazumat.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/fegerekaxowikanib.pdfIn PDF document text
    • http://bebsulmare.com/userfiles/files/zigosutodabaradewof.pdfIn PDF document text
    • http://inwama4.vn/webroot/img/files/57087451081.pdfIn PDF document text
    • http://dolekkoyum.com/admin/UserFiles/file/pajowivejagegalagisesaxa.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_off0000b5cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5CD 10828 bytes
SHA-256: e5cdca657bcf07a7cb045d84ae8dcd19fc3e0eb3f24a88989efb6718e1e99821
font_01_sfnt_off0000ceca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCECA 16132 bytes
SHA-256: bc809d7c30c44e4af8d32d0f0673c0f4fa3decb8169794313522ff03a413d456
font_02_sfnt_off0000f85c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF85C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1