Malicious PDF — malware analysis report

Static analysis result for SHA-256 c581884ae601d803…

MALICIOUS

PDF

84.2 KB Created: 2021-10-25 14:35:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 0e7127cc0eac6ff2d6f34988d83e0b60 SHA-1: e8420813db0851705f4d7a1274cba5f3d7e0b66c SHA-256: c581884ae601d803c02c3cace0b1e7e255948e6da1399882842c182e7ab8ed8a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links, many pointing to compromised or disposable hosting, suggesting a link farm used to redirect users. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://karlsbach.de/userfiles/files/16024194186.pdf In PDF document text
    • https://foundationkuzmanov.com/files/menutemukexikopo.pdfIn PDF document text
    • https://pasifikendustriyel.com/userfiles/file/tevufixatorawoxire.pdfIn PDF document text
    • http://autoservizimensi.it/images/fck/file/30316110498.pdfIn PDF document text
    • http://mariondhuique-mayer.com/data/file/sebemuvimogujuxejuwifupa.pdfIn PDF document text
    • https://bacninhonline.com/webroot/img/files/jetovexalosa.pdfIn PDF document text
    • http://ourpreferred.com/userfiles/files/98106814117.pdfIn PDF document text
    • http://polipack.ru/content/file/34127631761.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/7c006acfb75ae2accfd66dc2e595e51c/11462056594.pdfIn PDF document text
    • http://ehomerealestate.org/images/file/siruzi.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/91143878065.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/14662403915.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/161531ca297ad7---98858654703.pdfIn PDF document text
    • http://paradisoseminatrici.it/userfiles/files/44808509749.pdfIn PDF document text
    • http://ecolservizinettuno.com/userfiles/files/wumokudakubilafugom.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/fadff3ce497d806e8c53421cfa406776/45662935024.pdfIn PDF document text
    • https://www.hmgfinance.com/ckfinder/userfiles/files/woxurukivupolepi.pdfIn PDF document text
    • http://quangcaosms.org/media/ftp/file/40690252170.pdfIn PDF document text
    • http://tauben-buchmeier.de/ablage/userfiles/files/94471151787.pdfIn PDF document text
    • http://techmechengineers.com/uploads/majafakinogisut.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109201356539771.pdfIn PDF document text
    • http://lycee-elm.info/userfiles/file/monevegezexiwuwuligulo.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16148dc2494621---xapogobemotixoxax.pdfIn PDF document text
    • http://greatwalledmond.com/ckfinder/userfiles/files/85560733704.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/bofunajusuf.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021101103324073499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/HTGXzuRVGb4/uplcv?utm_term=the+four+hours+work+week+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_off0000e219.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE219 18876 bytes
SHA-256: 0cd810e27487c7c2991047a89e25ec5cb0dfa6d6783c38c802e7e4773b0f1694
font_01_sfnt_off00011375.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11375 10336 bytes
SHA-256: 7cecae5b78f1f35f4a817be266d3e9963049c3f897006fb8e4ae0f8d7b69e9dc
font_02_sfnt_off00012b03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1