Malicious PDF — malware analysis report

Static analysis result for SHA-256 78bf9cdf8eb71714…

MALICIOUS

PDF

80.9 KB Created: 2021-09-17 18:10:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d6ec0c1c6b80ca6983fc2743c945fc4d SHA-1: 04cfe6f69f3a6d8fdcb5df8a72884d8bcf70f802 SHA-256: 78bf9cdf8eb7171447e8c76dfd20e9af7d2bf8956672e367a5a82fcf5c7a5ae9
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://irlanc.ru/uplcv?utm_term=peer+e+kamil+novel+pdf+online+reading
    • https://jocafoto.com/fotos/file/zugukigavoguvizum.pdf
    • https://free-spirit-city.eu/uploads/wysiwyg/files/rerepofuxapufi.pdf
    • https://karolinanowak.com/userfiles/file/tunuwugutedavidokeju.pdf
    • https://cantellodetersiviprofessionali.it/uploads/file/marusipemugopepazope.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/8t4jcm0mkk10si1vjgj9c8i3ja/monokoritowidofola.pdf
    • http://qlinairnv.be/userfiles/file/diwuwatanarapotipubizus.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16140252e0303c---rezuwatozunesovabopev.pdf
    • http://gattoneva.pl/pages/userfiles/file/63699729458.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b700f7b452---2380423994.pdf
    • http://ekmeta.lt/failai/file/82827104370.pdf
    • https://flomogroup.com/upload/files/23408681910.pdf
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/67109a9e08eunsn5odiodonedr/78488278619.pdf
    • https://btegypt.com/file/22101841799.pdf
    • https://iqrainternationalschool.org/_assets/files/pebewukikijexugale.pdf
    • https://dammesliepas.lv/ckfinder/userfiles/files/16006620308.pdf
    • https://cafesca.mx/ckfinder/userfiles/files/89887966894.pdf
    • http://sentezetutmerkezi.com/upload/ckfinder/files/12028626311.pdf
    • https://goodline.by/userfiles/file/bafajujuloxofofasitun.pdf
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/surizovugomitabivaw.pdf
    • http://cbcom.fr/ressource/site-image/files/15208700620.pdf
    • http://centreforeffectivecoaching.com/media/file/91311748384.pdf
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/64306843166.pdf
    • https://hinaweb.com/upload/file/99277417883.pdf
    • https://artedeeducar.com.br/ckfinder/userfiles/files/xuwunolovukiwufogizesif.pdf
    • 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_off0000d83f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD83F 16792 bytes
font_01_sfnt_off0000f056.bin
546b7dfd3ce770b6b3ddb4ceb75c574f1f064f62c1d56b0d84781e3ac18e244d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF056 10732 bytes
font_02_sfnt_off000108b4.bin
224acfafd669ae4687bc28af4d17caa3965eb136a1347f579deea67fc44f70ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x108B4 17476 bytes