Malicious PDF — malware analysis report

Static analysis result for SHA-256 55474bd16dd66407…

MALICIOUS

PDF

89.3 KB Created: 2021-07-05 19:36:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 62508b26bc67b5c4b8aca19ff8b78021 SHA-1: 29e92b81fc106cc5f9e4be1f37343636097f975c SHA-256: 55474bd16dd66407d60b45f503c724569a4c08c9f49af88c8216508c01de6d44
204 Risk Score

Malware Insights

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

This PDF document employs social engineering by presenting a lure for browser extension or update installation, a common tactic to trick users into downloading malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the document's structure and embedded URLs suggest it is designed to facilitate the download of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • 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://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/nuu0okml1nuthh5gq2rd54hf68/38712495095.pdf In PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/f36dad21b2715933324724fa5e65e258/jugurinadafuvodezonujel.pdfIn PDF document text
    • http://www.humillacionyestrella.org/ckfinder/userfiles/files/46457018831.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa6ab5bbea5---garezimagomofaji.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/b3a707efff2a29cf8b5c0b4606d9c65a/mazibura.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/34071922092.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607def8b302e2---21629797718.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/puvoxupozaridap.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/fabc1375fe001f556d045bc5cae5b5c3/4416193445.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16092bc009c6b5---vagab.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071909c009b4---29170421007.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ccc76fba932---wakawovutofowuxoxunowaj.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/nmce98ihmd6mrn10q7hgj6cg5d/mukemekujeximaduzap.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/a56e7db80a8cbfcd289acb54ec0ab63f/1254525211.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7edfd87ed---fopinuvutizodubafedawo.pdfIn PDF document text
    • http://assistance.uz/images/shared/file/56568235963.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/notetanezovosatexikivosim.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/25lg15sact1phs38dbhhoqrons/42022752935.pdfIn PDF document text
    • http://sattamatkapatti.com/userfiles/file/14615658908.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/8d2bcba7b66fa412da25857729eb27cd/69989370647.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/robesumerazukam.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a42789ae4f0---11453681633.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/a0dddf8ea73ddf61796b2e27d6876fb5/litosupuderumisosipaturug.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16085fb0a21825---39488820362.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=download+ehi+file+for+http+injectorPDF 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_off0000f894.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF894 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000110ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110AB 10768 bytes
SHA-256: 0a411afcf94b3db415dd30c4ce552425916260a1366107ea444f1f091e577db0
font_02_sfnt_off00012955.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12955 17720 bytes
SHA-256: 9771438000827f90152ecc6673073ca2d7bfd8e5773eec7db5e9950559b0d5c4