Malicious PDF — malware analysis report

Static analysis result for SHA-256 871d8f2b45dfed16…

MALICIOUS

PDF

170.2 KB Created: 2021-07-03 10:44:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a1e741c2bff6bf18ba13898c183693d0 SHA-1: d2982e4955fca8edc48d86206a1c590f57b7f5da SHA-256: 871d8f2b45dfed1607ea257ddba5da31ed9cc5454eefe2b412ddd086b9159dcb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were directly extracted, the structure and URL patterns are consistent with malicious PDFs designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://bukvoznaika.ru/ckfinder/userfiles/files/renikisugoripo.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0ffff67a34---40560601881.pdf
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/ca3765919155e9c8d9f5e79519ab0399/14845888763.pdf
    • https://ildiko-szepsegszalon.hu/userfiles/file/jigudusorubusawu.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a4cd559f8a0---75692789144.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160acc6bcf0a6b---53538358306.pdf
    • http://retco.ge/ckfinder/userfiles/files/89440406348.pdf
    • https://dangeloremodeling.com/nbloom/fckuploads/file/44852977575.pdf
    • http://zaun-produzent.de/userfiles/file/66057151709.pdf
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfb7a0bfafe---52800670704.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160817f1887ee1---giraka.pdf
    • http://alpha-th.com/userfiles/file/76111364891.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/ff18c05477bea992647e14821afafe28/guruxazexilazaf.pdf
    • http://farmaciafici.com/userfiles/files/sasovorufojuwatosu.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/eff49e69a53e53b50fc8202993d49fbe/xinijufojofe.pdf
    • https://icbacademy.com/upload/files/840627314.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160877a3469cd7---11168794138.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd48a02ccb---vijavodiwejuravul.pdf
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/a8ctvkbepiq6h8k3vbkdurj61t/wibukudivulaxasedugexobi.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/0fniklird27j3cokk8irjpi3nl/sidanem.pdf
    • http://benedictinoselrosal.org/ckfinder/userfiles/files/30828414877.pdf
    • http://litho-and-co.fr/ckeditor/upload/files/xipumomesukutowakir.pdf
    • http://travelshops.pl/userfiles/file/tinumakadexafitirup.pdf
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/82906993738.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=arithmetic+and+geometric+calculator
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00023ae8.bin
b3c41b675c836cce18863c9cb9beeeab615dcb9f57444b6eabf7abf743b69b27
pdf-font-stream PDF embedded font (sfnt) at offset 0x23AE8 18072 bytes
font_01_sfnt_off00026a50.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x26A50 16792 bytes
font_02_sfnt_off00028267.bin
19cc394ace76e7f9ac19c657509fd5fd21756f706053743a0cfa476c1a1749d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x28267 10728 bytes