Malicious PDF — malware analysis report

Static analysis result for SHA-256 20ec205d999da6b0…

MALICIOUS

PDF

71.1 KB Created: 2021-09-26 17:32:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0628a8c7ceed2fe2152897d6d8318a7b SHA-1: 49fd5eb90a6df529edbc51873d26a1ef566be536 SHA-256: 20ec205d999da6b08449b9898eb76f0788822c00a7416ad7feb65ecf0a200550
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious document, potentially leveraging JavaScript for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://crewmak.ru/uplcv?utm_term=1337x+proxy+unblock+proxy+of+all+websites
    • http://marathon-gexin.com/Uploadfiles/files/55322156846.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1613d1d381f191---baxunik.pdf
    • http://xiangzhuan.tw/upload/files/tekaga.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16140618de903e---34173517075.pdf
    • https://mvpartners.be/images/uploadedimages/file/girixujet.pdf
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/jaretogesa.pdf
    • http://christ-china.com/filespath/files/20210905111713.pdf
    • http://md-servicios.com/userfiles/file/vikamovetepis.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161413d0954928---77356123938.pdf
    • http://travelshops.pl/userfiles/file/50329045747.pdf
    • http://dentalweek.eu/userfiles/files/71530968435.pdf
    • http://didopack.com/files/feruz.pdf
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/33149628832.pdf
    • https://andana.us/files/files/mesenulonujeso.pdf
    • https://www.phuketvillarentalandservices.com/ckfinder/userfiles/files/38262757525.pdf
    • http://elliptical-trainers.ru/ckfinder/userfiles/files/87389934064.pdf
    • https://doanhnghiepvietnam.org/img_duhoc/files/73443375779.pdf
    • http://slkuang.com/v15/Upload/file/202191035693542.pdf
    • http://bedrucken24.de/userfiles/file/4435848401.pdf
    • https://ssvacancy.com/ckfinder/userfiles/files/wezolanegijadidabefom.pdf
    • https://priscar.com/documents/files/tamovuzuruwefokukafa.pdf
    • http://strahyi.ru/images/file/55676488188.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_off0000b115.bin
0cf1c057fc3e01b9d7ad0f059bc34cf4c6470825737e3c33feaef7e50f62d548
pdf-font-stream PDF embedded font (sfnt) at offset 0xB115 11284 bytes
font_01_sfnt_off0000cbb0.bin
44ca25d41e3554160230c01ff3c692e2c8ae4ca945d6bf4aa8ce67732e6aec52
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB0 16664 bytes
font_02_sfnt_off0000f68b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF68B 16792 bytes