Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d9a9c223a746755…

MALICIOUS

PDF

84.2 KB Created: 2021-06-30 11:44:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 544ed0400b31d77ad8d4568df7986484 SHA-1: 9e4a4a29759f8122e907daf7612ec7bdb6541f30 SHA-256: 4d9a9c223a74675544938f2447eb6565ef5fb7ef26a0f2ea6a2767217ff4ac38
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS upload directories. The document body is heavily obfuscated and appears to be non-readable content, suggesting its primary purpose is to host these malicious links rather than convey information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://orig-shop-gsm.ro/ckfinder/userfiles/files/roriremupenewudilutabira.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160afe31ca15c2---62704248951.pdf
    • http://tebsc.com/clients/84181/File/loresagoxunuvagiv.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/jqecra3g0lvptlvkr3kqdoajou/zulukep.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9becb25ed1---ginanesoten.pdf
    • http://mdknoodles.co/uploads/files/vadogised.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/62bb981b374e9a85848e77cdbc1c88f3/4789042574.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b5ed1e1144f---3544820937.pdf
    • http://deurenhanger.nl/userfiles/file/21386338118.pdf
    • https://ilmercatinosottocasa.com/file/nobukerubuf.pdf
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16073d73308db8---tirabekalowefovawug.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160744194ee19a---bakemodekafakorom.pdf
    • http://pagyesa.org/userfiles/file/20210626032913.pdf
    • https://lwim-ouargla.dz/ar/files/86041639045.pdf
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/d98aa27741cad32d3c1f488a78df252f/nosiwokebobom.pdf
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074809c40529---jutalutixubetowezu.pdf
    • http://hondasushi.com/uploads/files/80284928359.pdf
    • http://charontrade.hu/data/file/99706883790.pdf
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/0c8afd77e11031be59145336c458d6c9/degejanonarupigegowobo.pdf
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/0a4e71527a41bc99a4464990704ed0e5/fuwikebizojedokomanaja.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087186a0488a---23709991183.pdf
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/17bb63003428c9a7707085aa3df4cbfb/48177875532.pdf
    • http://palyavalaszto.hu/teszt/upload/file/11567699696.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/gc8c39687kr9rk7rjr18mmmisb/rusufu.pdf
    • http://allprintusa.com/admin/images/file/lusirufawavelezef.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/n9sq0v5214l81r933pput1hei5/pakaw.pdf
    • https://angkortaxiservice.com/userfiles/file/1730497330.pdf
    • https://tavio.ru/files/file/47283099814.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=correspondence+education+meaning
    • 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_off0000e3e7.bin
4470c92012ef106a786a199f463089caa11caa6627c2efdb1496c1c025364629
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E7 17628 bytes
font_01_sfnt_off00011211.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11211 16792 bytes
font_02_sfnt_off00012a28.bin
ad60dec6419df06e116a88c89a59c7972dc17656c3e760675d8324d60408ed56
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A28 10940 bytes