Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b471789d6ed84d1…

MALICIOUS

PDF

91.4 KB Created: 2021-07-02 06:56:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c8ea6a1aab406e57c664aa5673b00d3b SHA-1: b94f769075c1fbe6e00e03abeb444c6f45a41128 SHA-256: 4b471789d6ed84d1408dd8946c080a50ac5b240e947ac2aaff4ce43bd8520926
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple distinct hosts, many of which are identified as compromised WordPress upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The primary function appears to be redirecting users through these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160796e40169f7---21605854945.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160de14207ba89---rabifozixazenevigujutax.pdf
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/4d27aef35a237d0a248a3668573d7bd1/kukupudeli.pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084231b34256---vabufoborutogatovagox.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/fda1dba36a90317a8c5f81fd0841d4c8/dawopajad.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a4df4eafd2d---tasalitapapufodipa.pdf
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/9cc8a7b1b330563757e460ce3e3585de/notivobe.pdf
    • http://kajsanordstrom.com/userfiles/files/37335314188.pdf
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/mnvm1nbu3evqajbfq93010fh64/77371304613.pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d037f2ff1b---pomefalodadufafufidof.pdf
    • https://alihuata.com/userfiles/file/xavodusizexogupilegol.pdf
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/g2d8hfb160mbhg8dkb12sui41h/28832939900.pdf
    • http://webinaris.biz/ckfinder/userfiles/publics/files/71410237572.pdf
    • https://detectiveoffice.net/userfiles/file/67807696024.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a6c6bbd7b---levadadedusunezolupaxu.pdf
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/ubuh9270p22lot4ojmon1hgn97/kikoganefiviw.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7tvog6a7dpv7pjea8tpj4ctue1/lomivuvekitavurole.pdf
    • https://aterhesseg.com/up_image/file/kesav.pdf
    • http://africa-emergence2019.com/userfiles/file/dakekutulivuser.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1d2d8d79b8---52078668001.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/1rhgp7ldaidgtg1n1jbmqm8c7j/dobunosekoxomako.pdf
    • https://sudhirsachdevaclasses.com/ci/userfiles/files/88280142828.pdf
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/7e1df9f9e53e86638fffef814b4f1e8c/nukulefawokimivebon.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d7eef4a26e---53502564952.pdf
    • https://hse.tw/upload/file/totemubobukopesilozape.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=do+cysts+itch
    • 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_off00010667.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10667 16792 bytes
font_01_sfnt_off00011e79.bin
bc22c9f1f21fe0089bb9b355becfcf9bd6f520bae0679786c7e388fc400aa993
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E79 17212 bytes
font_02_sfnt_off00014ae5.bin
be9f62af6444f56022c749a2273ee3b3881c9a5ff58aa12893a8b3b5b7b4e59c
pdf-font-stream PDF embedded font (sfnt) at offset 0x14AE5 9900 bytes