Malicious PDF — malware analysis report

Static analysis result for SHA-256 194ef163dae160bd…

MALICIOUS

PDF

81.2 KB Created: 2021-08-17 06:48:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a2c7891a796c3d93060c7c96f48b33da SHA-1: 4ab95977ad701e18d3d90364dbabb965fd8f5368 SHA-256: 194ef163dae160bdbfb0081f39b3a5b10175db21a2c8130ef726053b650908fe
204 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate maliciousness. The document's content, though heavily obfuscated, likely attempts to trick the user into downloading a malicious file by impersonating a necessary update or extension, aligning with a browser installation lure. The embedded URLs point to various compromised or disposable hosting sites, suggesting a distribution mechanism for further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://sgrdinstitutionspandher.org/sgrd/userfiles/file/2514585557.pdf
    • https://ntpuvoice.com/ckfinder/userfiles/files/49441563855.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609486658aaf0---26686201681.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/2ipefonh0rdvnvk9kk9ihnv0u1/tavokoteminubibub.pdf
    • http://busankid.com/webfiles/board/file///39358612230.pdf
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/56bc6e89ec754481d664275cf2ea5c7d/97337012978.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085382237f31---gufalufabugudinebomipif.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/9c77eca9b412e90d742aba3417229f3e/pizakumusen.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0b278e5249---fisapumilajidapogeg.pdf
    • https://everestart.com/images/stories/file/8694944838.pdf
    • http://dlmberatung.ch/userfiles/files/zakusumidi.pdf
    • http://446888.top/userfiles/file/derowunugekuduxip.pdf
    • http://wannawwannie.pl/userfiles/file/warevogi.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/fa9165ae9383f8e6d17e00f5cebd7a9c/40879566334.pdf
    • http://loaamtran.vn/files/usersfiles/files/46399649964.pdf
    • http://cityhelps.org/clients/6/61/61afa7a028a8e04f14432b0fece6f2b0/File/wofopuvafanaje.pdf
    • https://hondaotohaiphong.vn/upload/files/fijitafamuvirogebik.pdf
    • http://universalgroupautos.com/files/others/goleki.pdf
    • http://beautybybelief.com/admin/images/file/20710825981.pdf
    • http://planet-for-events.de/userfiles/file/2395032463.pdf
    • http://ytbozhuo.com/upload/file/200334488844.pdf
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607c9eb5ea798---tafiranatovutiv.pdf
    • http://cissi.it/userfiles/files/fuwuwutisariwuwol.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=adobe+flash+player+google+chrome+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d88d.bin
7a3323674fedf608647186a62b7cfbe384574ecd7ec420ef46cfc6ba000b6b4e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD88D 17304 bytes
font_01_sfnt_off00010581.bin
f0a8eb7dd6fd2b88aaac584c71fcbce357ac10038fd3dabc998ac544f37b153c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10581 11204 bytes
font_02_sfnt_off00011f2a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F2A 16792 bytes