Malicious PDF — malware analysis report

Static analysis result for SHA-256 f83cc008bd68101d…

MALICIOUS

PDF

91.4 KB Created: 2021-08-02 15:35:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4b1a74ed9ed5ee4da39e89904fbd9092 SHA-1: f9d019b1be02232c5c94b765e4b17634e1f6332d SHA-256: f83cc008bd68101d3ecfb25a10e932701a4c738c2f64a6e8e5f3669a74c44f5d
164 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded links, many pointing to compromised CMS upload directories, suggesting it functions as a link farm to distribute further malicious content. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.truckersplantparts.co.uk/ckfinder/userfiles/files/40935419427.pdf In PDF document text
    • http://collegium-connect.nl/ckupload/files/ponibinuvutijuwi.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c9080241b97---rizemuvorodefoteluvixisa.pdfIn PDF document text
    • http://accronline.com/userfiles/file/pewojekomeni.pdfIn PDF document text
    • http://partnerplus30.ru/images/fornews/files/tiropanoxereloli.pdfIn PDF document text
    • https://idd.no/ckfinder/userfiles/files/sopefesudasax.pdfIn PDF document text
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/36094062150.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160f31e5ee83e4---bamakutuwudezovelajumoma.pdfIn PDF document text
    • http://usarsenal.it/userfiles/files/polanogegobajex.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/cc46ebfa920e3521d478bd321b69d206/11714054888.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/scr0m7fusgthbqr84th9ig5nc0/25181747661.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c9c48392888---nitaronefafo.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad1983518d---moxowase.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b40f98ea14a---jikufetewupexabarakab.pdfIn PDF document text
    • http://myphamasia.net/upload/files/bopuxaje.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2fd1aa4989---19134738031.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/lebofibukasodibitajexor.pdfIn PDF document text
    • http://www.toptehnik.si/images/nudavexigewejezile.pdfIn PDF document text
    • https://promobryansk.ru/userfiles/files/nikeni.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/zazurufonumetoj.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/58560715332.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/16092efe769aa8---tekodemokitanel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=math+module+grade+7+3rd+quarter+teacher%27s+guidePDF 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_off0000f8fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8FD 11208 bytes
SHA-256: 4e3554efa91c0e4f9081bf0861c5599b1b6506d1aa2748c15173d9a57abf5979
font_01_sfnt_off000112d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112D7 19992 bytes
SHA-256: ccf92980a54db374157d8d769f4472df97accbd3374e3acb491c5723c64796e5
font_02_sfnt_off0001464b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1464B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1