Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfcb957e05a9a583…

MALICIOUS

PDF

83.9 KB Created: 2021-08-18 18:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 52289823b18abd8eb9fad06480e7535e SHA-1: 170b1b9ad6a2dff50649167f2abc57980a993f6d SHA-256: cfcb957e05a9a58352501b01a09b2d4690ffe4df4e9ddb49ebf42b4770452d30
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis point to a malicious PDF designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://cructi.ru/uplcv?utm_term=is+sodium+alginate+bad+for+you PDF link annotation
    • https://anthonygillant.com/userfiles/file/58268662260.pdfIn PDF document text
    • http://finpacecuador.com/userfiles/file/49550744633.pdfIn PDF document text
    • http://starlightcelebre.org/clients/4/43/43e9139217482d7666ce300faf566241/File/34520616317.pdfIn PDF document text
    • http://n2nlah.org/UserFiles/file/41816692384.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/69825765178.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/21410397619.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b116b202998---loporubibekot.pdfIn PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/83566534708.pdfIn PDF document text
    • http://nitexprofi.cz/userfiles/file/34050727795.pdfIn PDF document text
    • http://ketnoikienthuc.com/upload/files/89025587647.pdfIn PDF document text
    • http://muzeumostrowiec.pl/obrazy/file/94393749848.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/tulakulokifedugojadevo.pdfIn PDF document text
    • http://bptramptour.pl/files/file/bobifojota.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070d013e8545---41725445521.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/521d7696b9e504a164b060bb80c7eac1/jovonazorusojut.pdfIn PDF document text
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/digonobijukezeparox.pdfIn PDF document text
    • http://modamoda.nl/uploads/pic_lib/file/71473355811.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b220f97587---28282773387.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160cd6ff814e28---24188503914.pdfIn PDF document text
    • http://adice-area.com/pictures/files/36131317204.pdfIn PDF document text
    • http://thedreams.cz/files/sevabadajarowuwezijibut.pdfIn PDF document text
    • http://hasyo.net/files/file/78878274396.pdfIn PDF document text
    • http://sillajen.com/fckeditor/_upload/file/maledujesojilamezebo.pdfIn PDF document text
    • http://opakowania-loga.pl/zdjecia/fotki/file/88225988174.pdfIn PDF document text
    • 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_off0000e24e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE24E 11000 bytes
SHA-256: 7f59f31738f68e84de639bc8d6d0138df9819d034efb7098f494f7c2aa6dabad
font_01_sfnt_off0000fba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA8 17428 bytes
SHA-256: 5cc503a937fef06fa7d7edafe585b35ac17cdab3910eb055f22aa7049e06d95c
font_02_sfnt_off000128f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1