Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c4809d7a8328cf6…

MALICIOUS

PDF

84.0 KB Created: 2021-09-20 08:17:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f67b5494a4575f012791f008dea28eee SHA-1: 2c4258d04e8df8cd85f7a3fc036438a1c40d798b SHA-256: 6c4809d7a8328cf6643bb3df3bed8c9a3037fd7afdc56f1e1ae67251e226fc1d
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document is classified as malicious by ML and ClamAV, exhibiting characteristics of a callback phishing or tech-support scam. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting an attempt to host malicious content or redirect users. Although no scripts were explicitly extracted, the PDF structure and heuristic firings indicate a malicious intent to deceive the user, likely through a lure that prompts a phone call.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://krisoc.ru/uplcv?utm_term=uk+used+iphone+7+plus+64gb+price+in+nigeria
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/635f3588e0b8ae20b1ba2a324a6a3d29/76506404628.pdf
    • http://dinhviht.com/images/newtech/files/85552485545.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130648751229---jaxexafanivegefu.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614062b80e155---xikotemopolapep.pdf
    • https://rheinfurth.de/userfiles/file/68785029379.pdf
    • https://ahha.az/userfiles/file/wudalilowedejujobagis.pdf
    • https://himalmanpower.com/ckfinder/userfiles/files/sebukaveki.pdf
    • http://chithanhplastics.com/uploads/userfiles/file/88718030517.pdf
    • http://urs-certification.com/gais/image/file/52726182586.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0cbf5a780---juvadofefav.pdf
    • http://gbfrjournal.org/pds/userfiles/files/gufiwisuxinixepujes.pdf
    • http://iucecb.com/files/file/25080062646.pdf
    • http://www.superior-inkjet.com/login/ckfinder/userfiles/files/xiraxuw.pdf
    • http://secohthailand.com/file_media/file_image/file/webipeverawarus.pdf
    • http://boek.se/bilder_umeny/File/vosasebit.pdf
    • http://pmrs.ps/userfiles/file/fafarerutobusi.pdf
    • http://cuathepvangohaiduong.com/images/ckeditor/files/73927815919.pdf
    • https://kiofruits.com/admin/uploads/files/95612810841.pdf
    • http://to-tuong.com/media/ckfinder/files/rivaseposiliv.pdf
    • https://dildendilecevirievi.com/upload/ckfinder/files/50080981243.pdf
    • https://tavfelugyelet.megujuloenergiapark.hu/admin/ckfinder/userfiles/files/93655983956.pdf
    • http://ozkayalartrans.com/userfiles/file/36185944308.pdf
    • http://nesemlak.com/test/images/uploads/files/71000642821.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_off0000dfee.bin
1a23e77439b729c21db63bbbd45a6328f328cbc51226e730425c8f8aa4e5fa23
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFEE 18432 bytes
font_01_sfnt_off00010fb7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB7 16792 bytes
font_02_sfnt_off000127ce.bin
ad822f9af6ead71e0f1c8c398c0f6235a23ef1f334362b91fa68bfdedfa8dd8d
pdf-font-stream PDF embedded font (sfnt) at offset 0x127CE 11332 bytes