Malicious PDF — malware analysis report

Static analysis result for SHA-256 a10ebc70839e269f…

MALICIOUS

PDF

74.9 KB Created: 2021-09-22 22:33:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2053a6d2891d1edeced6410d0ea66ee5 SHA-1: 715467e0ed80714d54ab3ebd1426893f26edff9a SHA-256: a10ebc70839e269f77ed0ef34eb4480e3a6de8862916816d68572b3aef9ac73c
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

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://stamforgtechnologies.com/uploads/79374286573.pdf In PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/55400466570.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/bomuvaloguzagir.pdfIn PDF document text
    • http://philipwillettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wamazajakixulesat.pdfIn PDF document text
    • https://thaiahpa.com/flash/files/96223576870.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9f494637e---bejorarisamibibut.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/16139ca7e91cf5---40109802474.pdfIn PDF document text
    • http://davobio.com/upload/files/91708819701.pdfIn PDF document text
    • https://tidaksusah.com/contents/files/27301163407.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/89863824fcce58bf268df4c17e67a271/48112027974.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210912020258.pdfIn PDF document text
    • https://dienhoanghean.com/upload/ck/files/61313810660.pdfIn PDF document text
    • http://piqiso.ru/userfiles/file/8518861682.pdfIn PDF document text
    • http://hai-bi.com/uploads/files/202109101231491821.pdfIn PDF document text
    • http://harc-ias.vn/Images_upload/files/61713258954.pdfIn PDF document text
    • https://ubk-sad.de/azubi/userfiles/files/75687858844.pdfIn PDF document text
    • http://scandinavia-ex.com/images/blog/file/43095695432.pdfIn PDF document text
    • http://sromedical.com/file_media/file_image/file/70501995317.pdfIn PDF document text
    • https://kede.org/userfiles/file/3997014811.pdfIn PDF document text
    • http://vocal.bpv.su/content/files/files/4064573518.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/laguraxarugugejixapugut.pdfIn PDF document text
    • https://saptabangunmanunggal.com/indomobils/upload/file/61315092878.pdfIn PDF document text
    • http://xn--h49al71atridzo.com/userData/board/file/45992236039.pdfIn PDF document text
    • http://i-akparat.kz/ckfinder/userfiles/files/wilujufemawefidevuvo.pdfIn PDF document text
    • https://matrainagycsalados.hu/userfiles/file/sanumena.pdfIn PDF document text
    • http://cl-pub.com/files/files/lodojogenojupuzo.pdfIn PDF document text
    • http://chicopharm.com/upload/files/46676312559.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=file+manager+free+and+easily+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_off0000bff3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFF3 10804 bytes
SHA-256: 535ef054b527a7475ebd0b9459c72ab9c192a6503472f8a06180c3e5baadec06
font_01_sfnt_off0000d88c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD88C 17380 bytes
SHA-256: 2d1de3cee4ba27b4825eb4641ec94fef53b9d7c0ef8256f3e2d9b66f842eb725
font_02_sfnt_off00010575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10575 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1