Malicious PDF — malware analysis report

Static analysis result for SHA-256 d876d74b7d7fed4e…

MALICIOUS

PDF

80.5 KB Created: 2021-09-07 11:08:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 06170cac998b43c0c8ee987074e2b08a SHA-1: 09fe9ae9591e06bf7550b71beda5062833d8a928 SHA-256: d876d74b7d7fed4eead2c1cd4bd016a703867385e839de452481e0cd569299b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm hosted on compromised CMS uploads. The PDF contains numerous URLs pointing to various domains, many of which are associated with compromised WordPress sites, suggesting an attempt to distribute malicious content or phishing lures. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://autoneza.cz/UserFiles/File/revamuremujisixuzej.pdf In PDF document text
    • http://www.asslar.de/downloads/kowuj.pdfIn PDF document text
    • http://blbr365.com/userfiles/file/1624065274.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16082f1dd5d2fd---77896184135.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/29939380697.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/h019r9udf0hdn2gjdhav8kf247/podibebogasab.pdfIn PDF document text
    • https://felicitareonline.ro/ckfinder/userfiles/files/momunumijofava.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/c2it76btl68urjof6dgi551ag3/5472435221.pdfIn PDF document text
    • https://widerbet.pl/userfiles/file/11033862519.pdfIn PDF document text
    • http://dztechfin.com/upload/file///sumaraledixemet.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/43071826520.pdfIn PDF document text
    • http://webinside.pl/userfiles/file/47781932456.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/ruxigovirojuvop.pdfIn PDF document text
    • http://moskvaznaet.ru/upload/files/bureba.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/82a8dc411b5207d7e08b8b7972d45784/firowuguzuzar.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/186461f2f3f134596bab30d3fba33a41/12139156629.pdfIn PDF document text
    • http://fructusartis.com/i/File/piwisunumekevuxejevozon.pdfIn PDF document text
    • http://solemarservizi.it/userfiles/files/20214045607.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/68b9fc594d51fcc81cec1c1866777499/81494279753.pdfIn PDF document text
    • http://euredit-editions.com/userfiles/file/nusotewunapekefovuf.pdfIn PDF document text
    • http://arcenevents.nl/site/upload/files/kazojuxevunefokala.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/xijirifetasamipu.pdfIn PDF document text
    • http://roxburyhs1987.com/clients/63080/File/rinalefik.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/9725089995.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=como+adicionar+impressora+pdf+no+windows+7PDF 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_off0000d654.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD654 10804 bytes
SHA-256: 983bb9a4eee61e031ff65efa7ed14c14979f1618c49a1a823353770891fb970a
font_01_sfnt_off0000ef50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF50 17128 bytes
SHA-256: 25261f722789065431c028c0f3897541930abb12787c395a8b3423e301ae9599
font_02_sfnt_off00011bf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1