Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bc36d953598d693…

MALICIOUS

PDF

81.1 KB Created: 2021-09-07 00:11:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: fa0956393cecc2b3defed18b7c194ca6 SHA-1: 3457b37f6185ce3c5281d74829526bf4b4a42334 SHA-256: 6bc36d953598d6931a85ea5a4a88b78f24f3de4f7b7bb8236287d8f94f2d288f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm or SEO poisoning attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 https://krisoc.ru/uplcv?utm_term=infiniti+q60+manual+carmax PDF link annotation
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c15c913441e---14233085065.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/4884727035.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/govegaxowulanul.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160939ea35eca1---barorofidesosurajadud.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/wapisepakokoko.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/44148036030.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/70ea50687f66144f2798556034690315/62424661177.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160727e3458564---dagulinokowim.pdfIn PDF document text
    • https://taxforce.nl/userfiles/files/16013159130.pdfIn PDF document text
    • http://toeicspeaking.net/_UploadFile/Images/file/32236593430.pdfIn PDF document text
    • http://tienhasteel.com/app/webroot/upload/files/zubivurisagedikitebaxeg.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/15246596097.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160f73b6338cf4---sixebemanesuvaga.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/files/wuvitukikapifo.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/zazunutifaladapusibo.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7b75cd9053---77460530567.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160886416b059a---vumaralazopozugofelavexed.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/b545dc641534134286294725a32d8846/guziwoxusipizekilutodi.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/35bfc1bd4851390928aea4d5058c5f1e/levetivifi.pdfIn PDF document text
    • http://poorclarescork.ie/images/xaxixolarogizuril.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/3f24799bdb997b7b9f3b8150795683b5/73396151980.pdfIn PDF document text
    • https://alarouba.com/ckfinder/userfiles/files/mevabevaro.pdfIn PDF document text
    • http://mosjob.ru/images/file/22750589008.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/053943ae38ec8bb5f96558b1ec4fa956/30464327326.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/034b176057150c3cc7f4eec864f18791/99554611602.pdfIn PDF document text
    • https://siriusdynamics.com/assets/uploads/files/bedijawumakuwono.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d67b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD67B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE8D 18380 bytes
SHA-256: a61476449bd812b5e92a300c66de26c40cae955956bd634fbd264c1d7346c687
font_02_sfnt_off00011deb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DEB 10664 bytes
SHA-256: c84685941306d39ae025ae0132f3c200684242f99331e52bb783387628ae7548