Malicious PDF — malware analysis report

Static analysis result for SHA-256 9166e081c92b4efa…

MALICIOUS

PDF

84.9 KB Created: 2021-09-24 03:30:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 6897010f780a28a762054a7650dd85c7 SHA-1: 838ee302d206eec91692805aaf4ec4e36355d7a7 SHA-256: 9166e081c92b4efacbf62919752b7146fcf5c45ade8ef5097ab7ed35449c5cce
164 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm on disposable hosting. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. The presence of a 'download button' heuristic further suggests a malicious intent to lure users into clicking links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://tienphat.vn/imagesflashupload/file/niramumepaba.pdf In PDF document text
    • https://valerart.com/ckfinder/userfiles/files/2225764997.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161476a459f060---sawunadefeb.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161417f92b5dd1---jopok.pdfIn PDF document text
    • http://dezis.ru/uploads/files/nazaf.pdfIn PDF document text
    • https://www.hotel-restaurant-plainfaing.fr/ckfinder/userfiles/files/dexodabokapexala.pdfIn PDF document text
    • https://akvanova.ru/sites/default/files/25366774971.pdfIn PDF document text
    • https://arrad.ch/modules/ck/ckfinder/userfiles/files/xawofenef.pdfIn PDF document text
    • http://dennehylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/17397553480.pdfIn PDF document text
    • https://cs168.tw/upfiles/editor/files/zurugufumavam.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/79624271546.pdfIn PDF document text
    • http://dominant.name/userfiles/file/65368750473.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/78941704377.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/69974258936.pdfIn PDF document text
    • http://amsaneeraus.fi/userfiles/files/91934414222.pdfIn PDF document text
    • http://cs-golfclub.com/ckupload/files/tufamogojalekizedax.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/11243577287.pdfIn PDF document text
    • https://banderlogclub.ru/Files/file/31002596478.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/84751191332.pdfIn PDF document text
    • https://tgvl.in/uploads/fck/files/50877588887.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/8edc4da009427846f9def82363c2d032/jemigenovugixobodajo.pdfIn PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/96932261667.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=battle+chess+game+of+kings+download+apkPDF 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_off0000e2c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2C4 18700 bytes
SHA-256: 8474e5cdeb8ea0545f0e43b2454706131d43b26f19bff72567c9ad8d734d2e00
font_01_sfnt_off000113a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113A2 11200 bytes
SHA-256: 707055adf58e0ddbe20cff0af81ec8baca290993f61021622f0c139d3a3231a5
font_02_sfnt_off00012d93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D93 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1