Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a7e44e01069ae5f…

MALICIOUS

PDF

86.9 KB Created: 2021-07-16 10:50:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 36a76deb537f7eb6d1cf3ef5703f34e6 SHA-1: fb844c32785b5d69ef6da774e1dbcea72d084f92 SHA-256: 8a7e44e01069ae5f5adba8d0365e6fa3436079e25199fcb440bac844e9d49760
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites hosting other PDF files. This structure suggests a link farm designed to distribute malicious content or lead users to phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9e47e41e4---62118849333.pdf In PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/1f22e8022bb6ef129ddb1620af9b7d5b/kosimenegafudi.pdfIn PDF document text
    • https://eobliecky.sk/userfiles/file/17061943859.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/de0f76d7324b741c6068e1c0f93e5f0a/72809577860.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/70908743642.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1624447250.pdfIn PDF document text
    • http://samtekelektrik.com/files/wexoxivumuwa.pdfIn PDF document text
    • https://calendarsunrooms.com/userfiles/files/womanafajetobokedup.pdfIn PDF document text
    • https://phuketwebstudio.com/ckfinder/userfiles/files/65391846246.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a09cf7e6750---78751652437.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/32413987431.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee00a47cff3---98197593983.pdfIn PDF document text
    • http://srlamn.com/clients/0/00/00e84243199fd86ca7c15d66a0237eb0/File/lakatenimadideru.pdfIn PDF document text
    • http://dominoliberec.eu/images/file/files/90137360728.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/77082898204.pdfIn PDF document text
    • http://mientaytourist.com/uploads/files/disobo.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/5198226924.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/dce30d653b87df5e2275d9bdeab3c9b6/64877366460.pdfIn PDF document text
    • http://eia-edu.com/userfiles/file/59047700375.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/ffmg1n4lphhhsn0hpeum5a1497/35477910550.pdfIn PDF document text
    • http://aklond.com/UploadFilesfile///2021050711104636.pdfIn PDF document text
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f608e5a3d9---pigepavedekizuse.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=the+play+about+a+bank+robberyPDF 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_off0000ebcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCC 19964 bytes
SHA-256: 3543ce25fc45dd90a858a20ea17d5bee353ab9e4461286294c75242eec8ce59f
font_01_sfnt_off00011e83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001369a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1369A 10500 bytes
SHA-256: a237f12d55b0e9344f70e22cfc92f7ecafe5455abd6387ee8d99094da8b29f59