Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cd78889c86695e3…

MALICIOUS

PDF

94.3 KB Created: 2021-08-15 21:27:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 76f89d550607583b2253f6b331b4ca14 SHA-1: 28f2da724fcca90aeeb48dace7f23ad98b8da280 SHA-256: 4cd78889c86695e37a63333829cab8323fb96a712e95404db7941d220c9ca5f8
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress upload directories. These links likely serve as lures to phishing sites or downloaders for further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/9nu6h0mav9j07ol3o4d3eapa5v/tusakiboberafejidinu.pdf In PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ec9633bd903---wogusomewew.pdfIn PDF document text
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/c61c09a827fb3119eaf82600dc86d825/10695252132.pdfIn PDF document text
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/fp7g6n76d0qhgkbj1a0bmrmrlo/41426135653.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/abdfb7d663f0f3ce981bdc81af523be6/11878604953.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/8h15ageg6mkpl74taqlvhuegu6/55750051040.pdfIn PDF document text
    • http://bscartridge.com/pic/vamamodatinawoxisoweremor.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160969185d792b---sigijutikerulidagin.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/5a91111beb55f59fcea717b23ea53612/vuwogolurugosoniziguwu.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843e481df5f---visumafoxubibevijovubifuf.pdfIn PDF document text
    • http://barcabianca.eu/upload/file/86930294536.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ac692ca25f3---kuviseroramasufalovoweju.pdfIn PDF document text
    • http://xn--aknmedical-yub.com/uploads/file/tinovunamuxanoxo.pdfIn PDF document text
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/e4d162890896e36a60cca04fbef4ade8/jepojuwijinexokavufar.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/9d3195c020397866243fd4296828ab12/todadibip.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/pimuvozavuxalanexerir.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/89843945703.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076be79abfe7---pikezetesasinopirixiluju.pdfIn PDF document text
    • http://edwardfmcgintypa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/46547626839.pdfIn PDF document text
    • http://anandtouristcorporation.com/uploads/sugawoduragova.pdfIn PDF document text
    • http://koryosushi.com/uploads/files/93253880334.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/tagolagurolalevule.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/f8b5034b5aa3725b85e76dd74952ce4e/kofozerozonoreranevu.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607932ec4047e---rejalogutipidififepasupa.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116ad9cb3015---73201047621.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/8b88d6e86ed45a54b8bc0143f3f7ca60/65329059268.pdfIn PDF document text
    • http://altinay-law.com/images/file/gejazejoni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=which+is+better+honda+city+manual+or+cvtPDF 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_off00010cd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CD9 17112 bytes
SHA-256: c5b0e07f1a89033a198a6ee0d5156caf843f2eadf87dcb6bac93be331f3d700e
font_01_sfnt_off00013932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13932 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15149 11048 bytes
SHA-256: 1d79bc8c8b08bba786530fe7f3b7e59f83988e573cf0e0cc6805ad10d579230c