Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f63bbecee479b99…

MALICIOUS

PDF

84.5 KB Created: 2021-09-16 12:37:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 86d25655d8ffd5541ea19c0e2ebca363 SHA-1: 8c961d799c565f618ced532b3fbc7af928ecc9a2 SHA-256: 5f63bbecee479b992f755cfc454c87a275129a318f953cd00921b200b26e20fa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF contains numerous external URIs and link farms pointing to compromised WordPress sites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple PDF-specific heuristics related to URI links and compromised CMS uploads further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://nomylo.ru/uplcv?utm_term=safest+messaging+app+for+android PDF link annotation
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/6664027b0018eeece16c151a7a6c7f91/nejesizozasexedizag.pdfIn PDF document text
    • http://ghinelliarchitettura.it/userfiles/files/89640259321.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/50190220610.pdfIn PDF document text
    • http://aedjtjdshbf.pretty-match.com/upload/files/75017162160.pdfIn PDF document text
    • https://aleemanschools.org/userfiles/file/77233109055.pdfIn PDF document text
    • https://dichvuhappyhouse.com/upload/files/ruviz.pdfIn PDF document text
    • http://hennel.hu/sources/elemek/file/58912646248.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/86645c9ef4a6a36a1c52a15e29e86138/nizopinufuzumukepunekeka.pdfIn PDF document text
    • https://yenhuy.vn/upload/files/basidexe.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613020e8aa35e---vubaverow.pdfIn PDF document text
    • https://aquarell.ro/userfiles/file/zekipaxupema.pdfIn PDF document text
    • https://calmoinc.com/upload/editor/file/tutarobefoxinadizinunuk.pdfIn PDF document text
    • http://yongchengtech.com/uploads/files/202109080521006916.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/duluruwuteroso.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/qo2k7bg2fvak8rncn6su652ut8/5272559846.pdfIn PDF document text
    • http://builderall.info/userfiles/file/85627173629.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/wixewenakifu.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/77029361917.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/69190371449.pdfIn PDF document text
    • http://vonschickenfremont.com/uploads/files/gapodat.pdfIn PDF document text
    • https://noticky.net/akce/fotky/file/vozezewa.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/46226142485.pdfIn PDF document text
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/3613300137.pdfIn PDF document text
    • https://markiza-trade.ru/admin/ckfinder/userfiles/files/3365986836.pdfIn PDF document text
    • https://neurondevelopment.org/userfiles/file/fikagor.pdfIn PDF document text
    • 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_off0000e207.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE207 18628 bytes
SHA-256: 7a580c49eca6663821b108367823497d451b22b081cad9d9e2f06c93636bb4bb
font_01_sfnt_off0001137d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1137D 10872 bytes
SHA-256: 0c89f9aed8bb0ba9913bdee56eed38c07ee6ac96f939b3ad7ffc32f625230747
font_02_sfnt_off00012c56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1