Malicious PDF — malware analysis report

Static analysis result for SHA-256 53d5b3eff9bb5206…

MALICIOUS

PDF

86.6 KB Created: 2021-07-02 00:38:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dd5a5a766fbe73d85c3a298e9fc9dca9 SHA-1: a1f730700d85728878810394b07a6336b377217f SHA-256: 53d5b3eff9bb520611aa19f10328ce2e1af2939650ebedfbedec1b1d061f8c3c
156 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 or disposable domains, indicating a link farm or redirection scheme. The ClamAV detection as 'Pdf.Phishing.Trojan' and the ML classifier's high confidence score strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware distribution lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://study-go.info/wp-content/plugins/super-forms/uploads/php/files/4659fb4273b92a4fd45d5ea71e422a40/nudemefolofetedob.pdf
    • https://equator-maritime.com/userfiles/file/59544926019.pdf
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/de77qkk4n5gdevjcsp05d21urm/degujaxek.pdf
    • https://comobrew.com/newsite/images/user_uploads/file/zukepopomozov.pdf
    • http://archi1919.com/smlclub-files/file/vipunajerevij.pdf
    • http://apvn.info/userfiles/file/66830368023.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b50d941928---13525940880.pdf
    • http://aitrans.org/UploadFile/file/F1202105101517376899.pdf
    • http://55thocscompany.com/clients/62662/File/lujinelutejedesageka.pdf
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/286a5af0a6cea2a8936b3bce68895315/8873416484.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609baeaf2d0eb---67469423508.pdf
    • https://cleaner.pl/userfiles/file/wiladizifetu.pdf
    • https://aspaeng.com/files/image/files/27239527922.pdf
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/9jbguhfp68sjlecikr1h9lf757/gisezutezutafu.pdf
    • http://myappartement.de/web/editor/files/nufogip.pdf
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae382ed2ae---72470049647.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abd9ced45b9---83292841751.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160aecbff678d0---36768822478.pdf
    • https://honghow.com/ckfinder/userfiles/files/76485795524.pdf
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/da9a87608bd5ff9535ded81f3e3e29cc/70424824507.pdf
    • http://wskinbody.com/data/boardData/files/52889704147.pdf
    • http://toyteepee.com/uploadfiles/file/210627160516335535z0y4i9.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086d560f333c---66212020561.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=introduction+to+cybersecurity+final+quiz+answers
    • 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_off0000f0ec.bin
1fded6394a715d686a54f778530f9146dbb8e2196f988d3f75b23883d32620d1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0EC 16412 bytes
font_01_sfnt_off00011b17.bin
5c9ba7caddd8db189f32189f63870953193389283438cdc34e10d12b9a5f29d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B17 11064 bytes
font_02_sfnt_off000134ec.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x134EC 16792 bytes