Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc7caa0d784f7df0…

MALICIOUS

PDF

81.0 KB Created: 2021-09-05 10:25:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5c758acbf4b2d1175b93d656b5d8391f SHA-1: 3a20739602bcc454734e690353c269e9661c31d0 SHA-256: bc7caa0d784f7df007f925e397b26a72ec8798f09622dc20fd9ec19b34f2d8ff
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress installations, 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. The document body is heavily obfuscated and does not provide clear instructions, but the presence of multiple compromised URLs is a strong indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/c27cc89899a4e55751a47802d4e96f4f/82976001079.pdf In PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610b1c0c6630e---gopifikugu.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160943aa322cd3---lomewifo.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b971507590d---gedupovupexedupison.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/kupurimadorikobimikabevo.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c1c784cc5c7---sageb.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202105/file/zonirakeruze.pdfIn PDF document text
    • http://turinimoti.com/assets/userfiles/file/97653704068.pdfIn PDF document text
    • http://ropesadventure.com/d/files/77634276496.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607d8ea7d096e---dilogepofavi.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/25102463970.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/69394547243.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210821_BD5145DD54EC9CE7.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/zaputufijonixewoja.pdfIn PDF document text
    • http://thepnguyentran.com/media/ftp/file/9359108440.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a68f15aeb61---sixilegenase.pdfIn PDF document text
    • http://shbaicun.com/userfiles/file/2021073111514873499.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c0927fbf404---suvawonolalazo.pdfIn PDF document text
    • http://zonwering-belgie.eu/ckfinder/userfiles/files/97428794708.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/17137151172.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/futokevegamibonorila.pdfIn PDF document text
    • http://chi-kara.net/userfiles/file/berezadorotexudekegugap.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/pofenirulutoxirusofuxuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=indefinite+pronoun+exercises+with+answers+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_off0000d53f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53F 18424 bytes
SHA-256: 217efb1e7455d06b7dade9f4fbcabd6503415960188b37382174f6528f1ea17c
font_01_sfnt_off0001052e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052E 10908 bytes
SHA-256: a7fe09f0d90dd8f1277e871197f561a05bcbbd1d9a7797b023f70b8e2ae720b1
font_02_sfnt_off00011e76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1