Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a718cb2dff127f8…

MALICIOUS

PDF

82.8 KB Created: 2021-09-18 20:21:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e7ec10dc884d975d05dc9b67b0435495 SHA-1: 27f17ba6308ab1dc585b02c57c0df7e46e5e09b2 SHA-256: 3a718cb2dff127f84818edb52f349741165f2e3ac4dc29cff5b46e1c6ef7c90c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. It contains a link farm with numerous URLs, several of which point to compromised WordPress sites or disposable hosting, indicating an attempt to lure users to malicious content. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://finemetal-cn.com/upload/files/49875311643.pdf In PDF document text
    • http://kietminhrivet.com/upload/files/lerarabasesoxad.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/sibasosogewavugule.pdfIn PDF document text
    • http://xahscw.com/userfiles/file/zowapetof.pdfIn PDF document text
    • http://aviteksural.ru/admin/ckfinder/userfiles/files/wugituzivoxag.pdfIn PDF document text
    • https://posaonakosovu.com/ckfinder/userfiles/files/68520866231.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/vozubo.pdfIn PDF document text
    • http://geriatriccarenewjersey.com/userfiles/files/rawipijefapulumime.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f89152c837---50531692559.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/cdo73rpi2br8drgf2f2jprgqe8/wuxodafoselo.pdfIn PDF document text
    • http://mebel-moscow.com/content/xuploadimages/file/towudebolejidesupopuvug.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/wuwigibonumozetejazoroti.pdfIn PDF document text
    • https://www.ijdsir.com/ckfinder/userfiles/files/83385251515.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613db4cbb162e---13176991978.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/f642d9052eec2f695f40952554498bc3/garilojijoworifuzupa.pdfIn PDF document text
    • http://viral-list-machine.com/ckfinder/userfiles/publics/files/gurabijezapegudojanevafig.pdfIn PDF document text
    • https://tvsporedi.si/vsebina/farifapozanujixupa.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/gugaxeparufevo.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/53567583375.pdfIn PDF document text
    • http://ty-int.com/files/files/9393612745.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/dcd7b94714e68a1c084e6a1161e22cc6/23289736928.pdfIn PDF document text
    • http://supair-lux.hu/ckfinder/userfiles/files/ponurelamafuzimog.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/sijorami.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=sword+art+online+season+3+episode+1+englishPDF 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_off0000df40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF40 11056 bytes
SHA-256: a6dc334f5564eec8efd265baff42ec69c0d33f27c1a6d3348b0fd05bbbd5cef9
font_01_sfnt_off0000f8c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8C6 17296 bytes
SHA-256: bf8f32de3f3d6f0528ebedd5cfa6efbad8dcce1d4f0cd07d03c3c182d1dddeb6
font_02_sfnt_off0001250d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1250D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1