Malicious PDF — malware analysis report

Static analysis result for SHA-256 739786e27c76714f…

MALICIOUS

PDF

76.0 KB Created: 2021-09-08 06:44:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 458c6e2bb6c43524526e11f9c09122f8 SHA-1: 042111d66dabea8f2fc7c14d422a537db28da72d SHA-256: 739786e27c76714f85b241b66929ca9a3b0dacdc2b1a4e8fd61a942a1e91c735
156 Risk Score

Malware Insights

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

The file is a PDF document flagged by ClamAV as 'Pdf.Phishing.Trojan'. Static analysis revealed a link farm structure with numerous external URLs, some hosted on compromised CMS uploads. The ML classifier also strongly indicated maliciousness. While no scripts were extracted, the presence of multiple links to potentially malicious or SEO-manipulated content suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://evola.it/userfiles/files/53679979681.pdf In PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210629_213417.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e67692df17---goranu.pdfIn PDF document text
    • http://englandmatchshirts.com/assets/file/zuwelu.pdfIn PDF document text
    • http://shsuorui.com/uploadfiles/fckeditor/20210622/file/16243554833142.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/4e00bd181a4ed0d1b5e6236b7d966f39/64247188111.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16119b6af0ffb3---63123087203.pdfIn PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/sarikodafewi.pdfIn PDF document text
    • http://seashoresilverlabradors.com/clients/4/48/482fd9669fb3260065120a60ccac5e48/File/63083792654.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/sovokanujokuzem.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16096eb119291c---xaxugezusepura.pdfIn PDF document text
    • http://canadianrockies.info/files/file/gojifedidazotubu.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/15216857011.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/96882306167.pdfIn PDF document text
    • http://costanzolegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/51232588177.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/2d0b782ecf82b4ac9d582705dc5a9e7e/8835192011.pdfIn PDF document text
    • http://www.nbc.com.vn/ckfinder/userfiles/files/pejimonatepe.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021072422583091.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/fb32eeb2b619a0bd34ccbd386308d7a6/serun.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/msp0gsd2vsrjv08tush29626v3/1220294930.pdfIn PDF document text
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/6grgoaf8h1ut8idi52pu9n47h0/6486908051.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=dometic+capacitive+touch+thermostat+with+control+kit+cool%2Ffurnace+black+manualPDF 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_off0000c151.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC151 17788 bytes
SHA-256: 9da54227e00257df610add3d89efc96a030e3ecee3e4f45b401802388b5908f7
font_01_sfnt_off0000ef7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF7C 11264 bytes
SHA-256: efae41dc32a594f527a27fba0dfcffb4992c654b5533b507910820c50d91a8bf
font_02_sfnt_off000109a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1