Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b52d3836e04d998…

MALICIOUS

PDF

80.4 KB Created: 2021-09-13 01:16:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 53667886eee7f04cf01156e4443c16a2 SHA-1: e198a095786c5acf86b966b6f265dd0636ec6278 SHA-256: 9b52d3836e04d99874cf67858279959e6f83ef543abdc5e6bc9420c7a12d52b7
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to lead users to malicious content. ClamAV identified this as Pdf.Phishing.Trojan, and the ML classifier strongly agreed. The document body is heavily obfuscated and unreadable, but the heuristic firings and extensive URL list strongly suggest a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://pixomot.ru/uplcv?utm_term=when+i+look+down+i+get+dizzy PDF link annotation
    • http://squash-fitness.cz/userfiles/file/nufagofulidaw.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109032202594769.pdfIn PDF document text
    • https://stephan-kratt.de/data/reiterhof/userfiles/file/xizodefejat.pdfIn PDF document text
    • http://frezerovka.by/images/fxeditor/file/26137623526.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/041f7c747d555bc7067fa0daf23792f8/43821463020.pdfIn PDF document text
    • http://ordinate-ltd.com/file_media/file_image/file/savufunuzirorotokusiv.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f38583494---parasejonetove.pdfIn PDF document text
    • http://parmalab.it/userfiles/files/8478187743.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/56293465020ceb6094d5ca0143bd798f/xevebexiduwe.pdfIn PDF document text
    • http://xn--12cmi2byac9cdhd0hra6d7bxkwbgj1gch.com/user_img/files/37794993340.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/pejekokakejimukeg.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/43374133869.pdfIn PDF document text
    • http://patrickstaxi.fr/userfiles/file/wenexogajopudomaxuzokusov.pdfIn PDF document text
    • http://montpellier-businessplan.fr/mbp/upload/images/images/upload/ckfinder/gopidepop.pdfIn PDF document text
    • https://samsungdvm.net/upload/ckfinder/files/15432803972.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/6719d5094db124431ad2eaad88deeb0c/24016571789.pdfIn PDF document text
    • http://spokoino.ru/i/upload/files/88973864168.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/pobapuwixibox.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369b4c95683---15685687121.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/211f7a1357cea11e086bfea5475aaf11/duwugarejasojag.pdfIn PDF document text
    • https://rainbowprinter.com/app/webroot/files/file/4045111673.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/7d36fc5631f415de8ef505be95f79fd3/kalafodebapi.pdfIn PDF document text
    • 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_off0000d85c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD85C 10444 bytes
SHA-256: 8bde5d74c8bce7b6466f88238da129de53210c47ca3a600055837a27a9a192f9
font_01_sfnt_off0000efd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD0 16968 bytes
SHA-256: 42ee7433931ba15db5e2c1bacc5f97973470f74cfc93d704f3eed519ddd6d132
font_02_sfnt_off00011bc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1