Malicious PDF — malware analysis report

Static analysis result for SHA-256 4efb8da0a9c9c020…

MALICIOUS

PDF

76.9 KB Created: 2021-07-04 16:02:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 5f5235e0674a007ad498c0ef1e0d9393 SHA-1: 395ef251c52182f53df3d7bed6b3c712b3b2385e SHA-256: 4efb8da0a9c9c0204d3107618ecd67cd07f62bab7f1788c647114b67152a3557
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 upload directories and disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://doks-films.com/pcms/content/file/6439526017.pdf In PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/d53651333837ce3c41b176aa3c58a001/vukebis.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b4aa5eb88---nimavusizuvajatolisuj.pdfIn PDF document text
    • https://247hvac.ca/fabulous1/uploads/files/73049781789.pdfIn PDF document text
    • https://realestateconnect.us/wp-content/plugins/super-forms/uploads/php/files/opd77d09jg800b1guor0t6udu5/84362571419.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/efe5c1f5cec09cd6991f8343f1b22cae/tazareviw.pdfIn PDF document text
    • https://zlato-eu.cz/upload/files/wajedomibibamuxix.pdfIn PDF document text
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/b5984bba3827bb7a7456894c4f6f8936/lobekexuwif.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160882a0af0038---newiv.pdfIn PDF document text
    • http://banphimchuot.com/userfiles/file/mukififojuwaron.pdfIn PDF document text
    • http://aircond.md/upload_fck/file/58298800394.pdfIn PDF document text
    • https://www.brightfieldbusinesshub.co.uk/wp-content/plugins/super-forms/uploads/php/files/2obvd430hniovel0e9ufrlln5f/vajofapelelorilule.pdfIn PDF document text
    • http://teaandtiarasottawa.com/clients/e/e8/e8f54e69a7463df9fd0adff13cd8e90f/File/zelotokekinabuwaxed.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fbd253398b---solezutetewebureronunuzag.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/5baa175249a442dd7a760a13bad972c1/juxedemewu.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607af19971670---xomexoririjusizepip.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c1cb5daeb24---teterasosuvubatupajoz.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160704e7ba41b2---90687505450.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160c884805fb7f---94079100757.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1a2bbaabe---68708271322.pdfIn PDF document text
    • http://homenet-spb.ru/userfiles/file/66723184589.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16097492e63f57---10425702.pdfIn PDF document text
    • http://com123.vn/uploads/file/20060896930.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/0ea3ce7c412fef656a0f83c67353990b/dolutekenupawelid.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092cc14e5dfb---fojikewizatesi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=end+to+end+qosPDF 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_off0000cfc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC4 9972 bytes
SHA-256: 461f53cf753593bdc3748da5b79b2890bb728b324f633192ea45dd6015173e97
font_01_sfnt_off0000e5b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fdcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDCB 15864 bytes
SHA-256: 7c1e8793141f991587e4fd52e8c6c2bdc946941364681f539d90b3ba73f3fd6f