Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9712916034c7980…

MALICIOUS

PDF

70.7 KB Created: 2021-09-30 11:34:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 23b81b4e3f9f690d15160c8ddb3a9d84 SHA-1: 1634c23d0d375207e1520b7eac2366a4374c0d3f SHA-256: f9712916034c798039d782fec6136119110b42f3aa72dc3f720615325d739ce1
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the analysis relies on the URL heuristics and AV detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://ukonlinedirect.com/userfiles/files/56669458001.pdf In PDF document text
    • http://bamboomfi.com/htdocs/cljr/data/files/43032395790.pdfIn PDF document text
    • http://imcborivali.org/userfiles/file/9858296649.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/zapopibu.pdfIn PDF document text
    • https://vilnius.cvzona.lt/resources/img/files/54165301343.pdfIn PDF document text
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/rifosamiva.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/981dc972ee4ae4b64f24704c057ee69c/depivegavunones.pdfIn PDF document text
    • http://rogersdesignhouse.com/uploads/files/15785727193.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/16146401c6dc31---76875538462.pdfIn PDF document text
    • https://trystsalonri.com/images/file/3745032599.pdfIn PDF document text
    • https://pellevah.com/upload/files/81144332295.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/nafipi.pdfIn PDF document text
    • https://vinatech.com/userfiles/file/kemamowalinuterowoged.pdfIn PDF document text
    • https://bucatariizidite.ro/printuri-fi/files/68945606508.pdfIn PDF document text
    • https://lekkermooi.nl/userfiles/file/julejediluwemotejakam.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/t02fb5ij62a7gf9dcfletj8svf/37501760201.pdfIn PDF document text
    • https://profesa.net/userFilesfile/50247780795.pdfIn PDF document text
    • http://dreamsurgerycn.com/ckupload/files/towosu.pdfIn PDF document text
    • http://amkchem.com/upload/files/sekozuxaxinili.pdfIn PDF document text
    • http://thegioioto.store/upload/files/regenoxe.pdfIn PDF document text
    • http://helenhotel.vn/upload/files/vudotatitame.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/durovek.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/80178846831.pdfIn PDF document text
    • http://lso-msm.com/userfiles/file/rejot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=system+emoji+changerPDF 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_off0000b1fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1FB 16360 bytes
SHA-256: 70a2bad21186a39413fcd3ee52dc7aa29830ef0c0bcb478ac0eddbb0d78e4806
font_01_sfnt_off0000dbf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f40b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40B 10948 bytes
SHA-256: 2b2b9376dc156be174b527004cd861e092413adb7635c69f813ba80a986a51b2