Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd31101dd2c2bb31…

MALICIOUS

PDF

81.2 KB Created: 2021-09-18 09:45:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e78f6cd1f11dfa8e0dce42de1d1f0d75 SHA-1: 289e90c105b3e551ca1c4cb89cdd23ded9a3c976 SHA-256: cd31101dd2c2bb3132828cb9f1d07c3cf5e554f8f414953b8e29743f51c25871
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress uploads and disposable hosting, indicative of a phishing or scam lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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=snap+saver+app+android PDF link annotation
    • http://alpes-maritimes.proximeo.com/ckfinder/userfiles/files/ruwunavifavevevozo.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/21306228465.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/13317069209.pdfIn PDF document text
    • https://posh.hr/files/vuduge.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/pefusetagexu.pdfIn PDF document text
    • http://werder-ritter.de/UserFiles/File/binudemasofagopumekis.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161306d7d9c757---36224301902.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145489acd62e---43851174947.pdfIn PDF document text
    • http://studiotecnicopetrillo.eu/userfiles/files/viropenovekox.pdfIn PDF document text
    • https://laflammerouge.ch/userfiles/files/piwirulanovifaxolusa.pdfIn PDF document text
    • http://tootingtaxi.com/survey/userfiles/files/pokegixivewamokofe.pdfIn PDF document text
    • http://intertexmedical.com/userfiles/files/lepawolifumakoj.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/fujijufiwiw.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/dd70b798fbd517a4909157684fb36557/62800266426.pdfIn PDF document text
    • http://kientrucnhacuagio.com/upload/files/50441953002.pdfIn PDF document text
    • http://kompassztuki.pl/Image/files/51510950483.pdfIn PDF document text
    • http://mamam.by/upload/File/file/kedotefor.pdfIn PDF document text
    • http://islandpointfl.com/userimages/divipidup.pdfIn PDF document text
    • http://sinostandards.net/upload/files/83098635598.pdfIn PDF document text
    • https://swaarm.de/app/webroot/upload/files/67843012254.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/xukaxetopa.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/vumonikiwumorug.pdfIn PDF document text
    • http://realfootball.gr/userfiles/file/1968575799.pdfIn PDF document text
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/xobotapuseki.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_off0000d9f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F1 10380 bytes
SHA-256: abd3796028f2fd42a81a1e7bb3cd837b2fc741ef41caf8b53517b81e499885a3
font_01_sfnt_off0000f181.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF181 17744 bytes
SHA-256: ca5d4b3cd4d84d9a9a6357103ffee9f0c5b31d718392b262358196994b98e1a4
font_02_sfnt_off00011f5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1