Malicious PDF — malware analysis report

Static analysis result for SHA-256 14371a736e5b50db…

MALICIOUS

PDF

79.1 KB Created: 2021-09-15 11:15:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cfe445608a2dcae20b2c410b7503c815 SHA-1: 8a92d34e06b945643d89e5c082a3acdb0a71702f SHA-256: 14371a736e5b50dbb29c4d09e1f0f6b6b8dd364fbb248db4c4bb05ae476cd029
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating it is a phishing or trojan distribution attempt. It contains numerous links, many pointing to compromised WordPress uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific purpose beyond the link farm behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://am-system.eu/ckfinder/userfiles/files/femofosipijo.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133dc76475ec---30103605809.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/rofalupubu.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/a59a210a0f866e6d559ff198b05ba24d/53894216072.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/45900076966.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a19f9a7acc---51216262472.pdfIn PDF document text
    • https://www.assofmt.org/ckfinder/userfiles/files/9855354661.pdfIn PDF document text
    • http://ulsantour.com/FileData/ckfinder/files/20210913_299396888BBFB4A1.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd5359fd07---12107376277.pdfIn PDF document text
    • https://elmawadah.com/userfiles/file/patomoxifeku.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210904233825.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/wasaf.pdfIn PDF document text
    • https://norservis.com/files/files/39396492097.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/tawurarabed.pdfIn PDF document text
    • https://oasis-travel.ro/files/wevonigaz.pdfIn PDF document text
    • http://destockbaby.com/ckfinder/userfiles/files/figewalumiserozidawo.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb101cdd68---dojenu.pdfIn PDF document text
    • http://thevale.us/userimages/96687210730.pdfIn PDF document text
    • http://ttworld.hu/uploads/content_files/files/vexedunuzasesoxopafimu.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614168a20c264---zawalexudejupexamafetagik.pdfIn PDF document text
    • https://maharajganjtimes.com/assets/ckfinder/core/connector/php/uploads/files/6097237516.pdfIn PDF document text
    • http://golden-candies.ru/webroot/files/files/70382799429.pdfIn PDF document text
    • https://www.prieur-equipement.com/ckfinder/userfiles/files/rafexisiz.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/0h6g5vrudtfjnpt3stpps0dko7/67896597452.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137ba0936151---dasimusunugo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=best+simple+keyboard+for+androidPDF 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_off0000cfb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFB0 17480 bytes
SHA-256: 64c576d4e0970783027c56f8b33ce7e7a3731c846fabf5d3c90a2d539789a800
font_01_sfnt_off0000fd1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011535.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11535 11056 bytes
SHA-256: e42ea7023827d4a2073c8d12ddd1bae37938fb2d839d22b02b4cd5391e1a6b2a