Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6bf7b135d685dba…

MALICIOUS

PDF

94.4 KB Created: 2021-08-14 03:21:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a675b323b3b681c6f59dd9cea2fad16c SHA-1: b8d672c1a2417f5b90b6e241c34c33f6724d1472 SHA-256: b6bf7b135d685dba78cb6542c87db0abebd145b4fffae5880f818c70abf416bd
212 Risk Score

Malware Insights

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

This PDF document employs a fake CAPTCHA lure to trick users into interacting with malicious links, likely leading to further malware downloads or phishing. The embedded JavaScript stream and numerous links to compromised or disposable hosting sites indicate a clear intent to distribute malicious content. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 9

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/d7080ad8cbcb924824901e25b8496e2a/85698001709.pdf In PDF document text
    • http://3e-machinery.ru/app/webroot/filesfiles/20891386202.pdfIn PDF document text
    • http://elanaclub.ru/userfiles/file/nupumebemed.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/efd7a839f295e5f1bd488a80cb54ad36/gelanewegegutaxoremuvafa.pdfIn PDF document text
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210527053610209130aigbtr.pdfIn PDF document text
    • http://ecole.ru/text/images/file/18114487606.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/68498584758.pdfIn PDF document text
    • https://stka.gr/ckfinder/userfiles/files/xulosepe.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/1o9veqes9086919tdpose467lm/dijowumobuforan.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/cf14eeb28fe6abc497170a8e044e947b/23070880791.pdfIn PDF document text
    • http://www.dagmarsvendova.cz/admin/js/ckfinder/userfiles/files/naworemim.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160751a8d82250---12708819792.pdfIn PDF document text
    • http://tomei4x4.jp/js/upload/files/tamexipototowo.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/16080883639f32---90209649314.pdfIn PDF document text
    • http://residencelesaline.it/userfiles/files/4589085240.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/39012470506.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/091952581218.pdfIn PDF document text
    • http://ydchem.cn/filespath/files/20210730053218.pdfIn PDF document text
    • http://unicaconsultoriarh.com/images/files/musopomazipibivijenipifel.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/161005cf259edc---zukevifinuvawed.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/75465077bc6e39b323fad42c8d17a663/xafoni.pdfIn PDF document text
    • https://aljazeerahpetroleum.ae/userfiles/files/65873662890.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=super+smash+bros+ultimate+apk+free+download+androidPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e0a74ba2533---relomokegux.pdfIn PDF document text
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF439 16168 bytes
SHA-256: 2f088311e3cc47affea05821c2def65328b1f74a195200b1b3e81469be6e99d2
font_01_sfnt_off000109db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DB 11256 bytes
SHA-256: 55dbaa6d33f422faa13a222808379407bd6a826e2d7f5e53dd44af2f4b73ece4
font_02_sfnt_off000123d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123D9 17748 bytes
SHA-256: e27d68348382d4746d2a05787cfc831126f3cc8e9a69bf17a71c25e5c4d4e5b2
font_03_sfnt_off0001527b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1527B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.