Malicious PDF — malware analysis report

Static analysis result for SHA-256 da3467e1382cf4d8…

MALICIOUS

PDF

78.9 KB Created: 2021-09-06 21:55:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: d709e80d16843c0e9b9814478f69d0d7 SHA-1: 6daa379a380b8becd6dd67f50cec9d2befbb9452 SHA-256: da3467e1382cf4d8481735c3d06fcd312f428d9b67554500dc08872ca2998d70
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, indicating it is not intended for human consumption but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://nomylo.ru/uplcv?utm_term=p+block+elements+notes+pdf+download PDF link annotation
    • http://el-master.ru/userfiles/file/70007817036.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/gotuwe.pdfIn PDF document text
    • https://ingatlansos.hu/images/userfiles/file/87304954552.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c899171580a---78989906739.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/3836978874.pdfIn PDF document text
    • http://fluellentrees.com/clients/58222/File/somokafejiguz.pdfIn PDF document text
    • https://motiv8workout.com/up/files/41922686602.pdfIn PDF document text
    • http://ozdoby-betonowe21.pl/Upload/file/8520539650.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8935ec14ac---vixopezafadisuxi.pdfIn PDF document text
    • https://handientu.vn/userfiles/file/lapererezed.pdfIn PDF document text
    • https://csn-alliance.com/data/files/lelikosami.pdfIn PDF document text
    • https://pablohernandes.com/wp-content/plugins/super-forms/uploads/php/files/d09fe58173cb38b80b0322103739df3d/4855806433.pdfIn PDF document text
    • https://gilbertems.com/videos/file/85075264653.pdfIn PDF document text
    • https://consultingexpert.eu/fckeditor/userfiles/file/51262869094.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/25691400283.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/79873314175.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071ca2bbdd27---18996647599.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ccmrargtk581ev0stii21ro3c3/kifamovatosexuzilubovol.pdfIn PDF document text
    • http://nwatchonline.net/userfiles/file/69856389202.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a25439688a---guzekidupif.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/t2trgtlv4fllnehd0lcfbl6gmf/22651256042.pdfIn PDF document text
    • https://chmelo.hu/sites/default/files/file/16436706398.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b4cf2aace828b27339ede75bc5a18576/bawuzudugimomaraje.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a31edf2d424---73429968136.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_off0000d021.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD021 10908 bytes
SHA-256: d42243e9291ed0513810018e0f8617b6abed3580c875ac961835cffc090c0592
font_01_sfnt_off0000e948.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE948 17192 bytes
SHA-256: beee6d5d764d107479e3f1056278bab4b800d874226bd68b28722c1d2ae89e2f
font_02_sfnt_off00011588.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11588 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1