Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c64dfd7644429a7…

MALICIOUS

PDF

85.0 KB Created: 2021-06-27 16:30:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 5ac6547025ab6ecaa19870684ee99644 SHA-1: ec653d016f74d63ed8508478df19d264b997883b SHA-256: 4c64dfd7644429a705b106d06fe0bb55862b96273450ac4005bd034296673583
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous links pointing to compromised WordPress upload directories, indicating it functions as a link farm. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification yielded a high probability of maliciousness. The primary purpose appears to be directing users to malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb28fb6b63---mazabimubenujeruki.pdf In PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bca030bcd6c---donodogibumelusuwukowera.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/rivoxefebaxemenanon.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/78391647449.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d77c5143a8---sezikususapezukeweriv.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a6e29c291d---zanoguxatokuf.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/d3c3279df11864ec243396a6db95ecbe/pufisaxuk.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/a52ecdc85d2ab6852965d08a836327ed/54070784957.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/295037de8f0b3c216a9dd93e949081ea/zijodu.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/vifafibuw.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f328001ce3---4480435505.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/k1ht8lbh9j9vbc84sb7sukulc3/89082069255.pdfIn PDF document text
    • https://reniuved.it/file/tofotutodebovivorimuv.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/84192846707.pdfIn PDF document text
    • http://kubabus.cz/novy-web/upload/file/10416067274.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089ef2e5d3ab---jopigasaduradu.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/pagotenawevod.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c512f3b4d89743e7994da352aa5407f1/89541231915.pdfIn PDF document text
    • http://beiks.info/public/file/65205416665.pdfIn PDF document text
    • https://antae.be/app/webroot/uploads/file/wezozizulaxuvugedakimegad.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160722fa4a914d---32766409890.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b1cddc4ab---gawuniw.pdfIn PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/dukelivonos.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16087133fc818a---44498711247.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e54ce8b55---sirimexipojubesojelava.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/ds7clk69m6riokufem11qsvgr5/denoxetebizojafuvem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=new+cv+format+2020+word+free+downloadPDF 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_off0000ea26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001023d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023D 10748 bytes
SHA-256: e8cabe49f3530516b158f8303f3ef408ff17201a536057729ad0773a9a86db86
font_02_sfnt_off00011b17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B17 16780 bytes
SHA-256: ac9867d136c8e73f17b3577ae85807a116beeb1729b76ee79f818e8b8ac1eba1