Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdf924d1edfbfc42…

MALICIOUS

PDF

94.5 KB Created: 2021-07-17 21:07:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4bfebee8efe945e454da0d5d993a3921 SHA-1: ab379f3b79e8a7c379fca582c88dce7fb8958df5 SHA-256: cdf924d1edfbfc42131e46583eb082055b99dcb5c1ebcdfc3e34bad421bb89d7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. Heuristics indicate the PDF acts as a link farm, pointing to multiple compromised or disposable domains, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://messtores.ca/fck_user_files/file/judunoneselorezedilibibir.pdf
    • https://ancoraeducacion.com/images/67619995417.pdf
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/1a37425a1ce1dbdd69ab7ded71bf391c/79412134240.pdf
    • http://am-assets.com/aom/magnolia/userfiles/file/53036935399.pdf
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/160b3bd8ddbcad---megudadoxufa.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/396m1bhcs0e8nsar9r2fvvv1m2/vedox.pdf
    • http://studionegrelli.it/userfiles/files/21323241378.pdf
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160881b090c316---bixafisosereratejigalova.pdf
    • https://jajugroup.com/ckfinder/userfiles/files/jatowojexefexowor.pdf
    • https://ikansambel.com/contents//files/dedazuxufujo.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1b839a23f8---60964480650.pdf
    • https://abhimaninteriors.com/ckfinder/userfiles/files/nutizuvowu.pdf
    • https://kodcomputers.ro/2664/uploads/kuliwamavidaxom.pdf
    • http://phuocthuan.vn/images/pic/file/32920111905.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a750d1f1e6---dikunoriwu.pdf
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/ulco7ftbrhsk81u5er3scvjve0/72462776564.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/17c0718cd6ee7554cf82e900c3d52ee6/wazulexetomeninux.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/e9b6f41d3268ec518c84bf8be827ae8f/nulaso.pdf
    • http://cnc-soustruzeni.cz/files/file/fanev.pdf
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/ivllr4hblbi057r8rb402len03/49538246838.pdf
    • https://goodline.by/userfiles/file/20450199666.pdf
    • http://perechen-jurnalov.ru/js/ckfinder/userfiles/files/79667649240.pdf
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/ce194e7e7fb75e1ff7bea2bf5a9758d4/9206486788.pdf
    • http://katyababash.com/images/uploads/file/pubiveg.pdf
    • http://packturf.fr/files/lisutugogavukani.pdf
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160874cce4c38d---jonipakipixup.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=anthropological+perspective+on+social+change
    • 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_off00011205.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11205 16792 bytes
font_01_sfnt_off00012a1c.bin
c524fbfea9729ac67eca8dbdf87169b50dffc9671188c3b0ed4119831e368262
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A1C 10700 bytes
font_02_sfnt_off000142a9.bin
3d83553148462edfeed140200041aa85fe69f0d356a736b737332120459dd438
pdf-font-stream PDF embedded font (sfnt) at offset 0x142A9 16464 bytes