Malicious PDF — malware analysis report

Static analysis result for SHA-256 20f7fe22f4fac871…

MALICIOUS

PDF

68.0 KB Created: 2021-09-26 19:01:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 31ad25ff4132f602479a6d00d5601872 SHA-1: dc64558af62d2872fa84dfbd25de3b7be904c7bb SHA-256: 20f7fe22f4fac871b510cb63e98304303a09648f33a6136baab5dcbc9d9f5481
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The presence of numerous links, including one hosted on a compromised CMS upload directory, strongly suggests an intent to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://cuanhuadanang.vn/uploads/image/files/72517253106.pdf
    • http://agrostroi-proekt.ru/ckfinder/userfiles/files/55060498835.pdf
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/50780614294.pdf
    • https://beysukonaklari.com/ckfinder/userfiles/files/68017456945.pdf
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/nvc0k15abkv5o938pnglbi53oe/vuwijipufodewiwi.pdf
    • https://infiniteprospects.com/FCKeditor/file/19507115916.pdf
    • http://evo-models.com/uploads/userfiles/files/munefoxomamazusa.pdf
    • http://dogable.de/userfiles/file/sirigo.pdf
    • https://isleo.com/i_photos/file/sezirusakabodokatemavo.pdf
    • https://hophamthaibinh.com/upload/files/wiwixelu.pdf
    • https://maturana.cl/upload/file/36820876539.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/b889e87b185889469f7e8b7850a11ef7/33361765221.pdf
    • http://aescantabria.es/upload/fckeditor/file///zurobogojivomigavinizo.pdf
    • http://biemmecommerciale.eu/userfiles/files/vagemerabenef.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/jvcfi3ub9rje2biq4i2m7dc5je/26601554523.pdf
    • http://avs-market.ru/admin/ckfinder/userfiles/files/38449676756.pdf
    • https://sunsoftinfoway.net/ckfinder/userfiles/files/lipukosiv.pdf
    • https://www.asoriofrio.org/ckfinder/userfiles/files/58768743233.pdf
    • http://daehnfeldt.com/userfiles/file/38180128826.pdf
    • http://allamericannursing.com/userfiles/file/10149161151.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/5636158928d3f3a5e82edd3dcb6c39de/39712882883.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=download+game+bully+original
    • 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_off0000ac8d.bin
cc2cb548925a0748f59466f71a2b8263cd2536241b3dc1af7dcf748dcc53c3e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xAC8D 10764 bytes
font_01_sfnt_off0000c50d.bin
03d3d243a8d668b3e522797cf42045ddfd371618416abad9b8f8f6ccf5d2fd5e
pdf-font-stream PDF embedded font (sfnt) at offset 0xC50D 15020 bytes
font_02_sfnt_off0000eaad.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAAD 16792 bytes