Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b4dfb85e229e89c…

MALICIOUS

PDF

71.6 KB Created: 2021-09-06 16:29:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6d04d091888b51ad3cdc3d22c267ee13 SHA-1: deeb083cc68451484aa597a068ae5dac88d7b183 SHA-256: 3b4dfb85e229e89c29be4f5a8d8aa5dc2d6bc9d7f31e191270be2788f077d46e
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan', and an ML classifier indicating maliciousness. It functions as a link farm, with many URLs pointing to potentially compromised websites or disposable hosting, suggesting an attempt to lure users to malicious content. The presence of numerous links on compromised CMS upload storage indicates a sophisticated distribution method.

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://finproekt-msk.ru/userfiles/file/28706469158.pdf In PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/897c600f86acc286cdc4e48fd6e4015e/19632881174.pdfIn PDF document text
    • http://dsagco.com/Upload/file/rugojojesugefiwasezes.pdfIn PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/73061877012.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/71840147291.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/70171023236.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/8c207de62fc1591ad125ea66af757dab/rutujomitunavusamawupik.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/57216149008.pdfIn PDF document text
    • https://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/rh289pit6pc5a8mbokbdnv6fv4/xijezorakexozuvuv.pdfIn PDF document text
    • http://nfc.soo.jp/file/82294626360.pdfIn PDF document text
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/nabudemin.pdfIn PDF document text
    • http://dlzj.net/upload/files/20210623034711400599.pdfIn PDF document text
    • https://2acontractor.it/images/file/59691676716.pdfIn PDF document text
    • http://kientrucsangtrong.com/plus/files/48464486915.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/160488441.pdfIn PDF document text
    • http://www.cbs-emballages.com/upload/file/lisemopaxozoruluzapipev.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/namunuvulamesigurilat.pdfIn PDF document text
    • https://thegioibaobicarton.com/Images_upload/files/62364978782.pdfIn PDF document text
    • http://mpu-beratung-brendle.de/userfiles/file/katoter.pdfIn PDF document text
    • http://www.halpellet.hu/userfiles/files/jabepurevimopikibegora.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/18ab219d426775dd19d5a7013fdc87ad/dabapuzemugogimepav.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a9cfc5d83cf---96807562593.pdfIn PDF document text
    • http://vrieshorst.nl/images/uploads/file/36089132883.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=skullcandy+indy+owners+manualPDF 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_off0000b7d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7D0 10900 bytes
SHA-256: 0735a0ef91d6b13ed13754e920e723706ebd3c460415a054455dfbbfb214c1b1
font_01_sfnt_off0000d112.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD112 15684 bytes
SHA-256: 75bdd95d2b8ab79eb5693c88735a7a1c4ee062efcb077503ee9f624e790a2d16
font_02_sfnt_off0000f918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF918 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1