Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e1f1865b94e38eb…

MALICIOUS

PDF

77.9 KB Created: 2021-09-18 06:50:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fca0a41c404850ea88df79d6ed583807 SHA-1: 9a926159b62f2b79ace15124e60d91e35d89a24d SHA-256: 8e1f1865b94e38eb316a41aab31133eb46603702395942bf0486f46bf4dfa46a
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. Heuristics indicate it functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body is largely unreadable binary data, typical of obfuscated PDF content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://krisoc.ru/uplcv?utm_term=itext+parse+pdf
    • https://mycocoa.org/images/upload/files/miparonuvusoxagudona.pdf
    • https://kvizek.hu/ckfinder/userfiles/files/kutewa.pdf
    • https://whatproperty.ng/ckfinder/userfiles/files/96483838238.pdf
    • https://grupahatak.pl/admin/_fck_files/file/22299774918.pdf
    • http://trongtinpc.com/luutru/files/malogazuwipobebozudases.pdf
    • https://dmitrovka-zn.ru/admin/ckfinder/userfiles/files/tajez.pdf
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/a08c3f453ca770ca4d21f585056b3b4b/kefoxixukulomowapemetaf.pdf
    • http://em-mould.com/ckfinder/userfiles/files/tekosapulotiporukupezedoj.pdf
    • http://iberia-ex.com/images/blog/file/14498841942.pdf
    • http://share-world.tw/userfiles/file/faxilexubunidurageme.pdf
    • http://loveperfectionschool.com/upload/file/rafewigonol.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/b6b4d32b0bcf2deab8c3a55a11cf1d73/25735808815.pdf
    • http://poltinka.ru/userfiles/file/siwowiz.pdf
    • http://homeopathyhongkong.org/files/wafusebotol.pdf
    • http://net-work.cz/data/file/jijive.pdf
    • http://robedecreateur.com/img/files/48227604099.pdf
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/30328833217.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba7d13f932---67050776607.pdf
    • http://iwort.de/userfiles/file/47568981472.pdf
    • https://gulamanis.com/contents/files/minilo.pdf
    • http://zpkprzemysl.pl/ckfinder/userfiles/files/varozajewamegabelokapab.pdf
    • http://uralcomservis.ru/crn_fls/crn_files/gazutibuladipu.pdf
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/ac3f32bd4a5886cd81279559e229e0d9/winixasi.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/16140903c5f506---demininunulijuwije.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ccca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCCA 16792 bytes
font_01_sfnt_off0000e4dc.bin
a1e1278fc2826bcdc3b679a9fa459e22a0c303e5f0237944f901d24b4b3c331b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DC 17760 bytes
font_02_sfnt_off00011353.bin
8ef4d6d39dcc1980d6973fd625346ef8df9ba22916e9590daaafdad6d90f6519
pdf-font-stream PDF embedded font (sfnt) at offset 0x11353 10184 bytes