Malicious PDF — malware analysis report

Static analysis result for SHA-256 8de7aebcb24d28c1…

MALICIOUS

PDF

69.2 KB Created: 2021-09-27 10:03:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ce5432a376176e5d2f78b34e07a6400f SHA-1: e280884d769ee6e02d58a24e96888452c0b825ab SHA-256: 8de7aebcb24d28c119afb56dba20955afbd32182d88f15856549cb5415dbe38a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, suggesting a phishing or malware distribution campaign. The presence of embedded URLs and the nature of the heuristics indicate an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://queure.ru/uplcv?utm_term=download+a+instagram+reel
    • http://tolltisztitas.eu/userfiles/files/tofodazexavig.pdf
    • http://secureyun.cn/uploadfile/file///2021092009035744.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/iddcr3u9lqtnl52uise92e88k1/95549575575.pdf
    • http://aczelzalog.hu/tmp/35902035329.pdf
    • http://csc020.com/userfiles/file/20210910220331_4jnosp.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16134b87e987bd---tekulixetuzawoxiwumome.pdf
    • http://pibar.tw/uploads/files/202109202033359222.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161339975a8f82---31343076524.pdf
    • https://arendic.cl/files/zutijojogukuvowakoka.pdf
    • http://turhantur.com/turhantur/files/52321596864.pdf
    • https://wcfkenzi.com/ckfinder/userfiles/files/zenetonot.pdf
    • https://rolcsi-bau.hu/userfiles/files/45807352498.pdf
    • http://energy-labels.com/userfiles/file/16397464465.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4412a661fab969064cc7e3b698725fff/18275588925.pdf
    • https://byocamacho.com/ckfinder/userfiles/files/68808686002.pdf
    • http://www.alliance-bio.com/user_data/editor/ckfinder/core/connector/php/upload/files/vebumiw.pdf
    • https://chokysitohang.com/Uploads/userfiles/files/26588392110.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613f9d77bcc57---gaxupiwuz.pdf
    • http://shanghaiqingchen.com/upload/files/sizomifisafapamisoxijubax.pdf
    • https://cosmopolitanhotel.lastrada.bg/uploads/wysiwyg/files/43171033832.pdf
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/vinibiriraxiligisubiv.pdf
    • http://cuacuonnhanh.vn/Images_upload/files/66036064075.pdf
    • http://chikatere.com/Upload/files/jupexufikogajisuwu.pdf
    • http://emachn.com/data/attachment/file/31771594039.pdf
    • https://steammining.com/userfiles/file/talosajoli.pdf
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/87692321303.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_off0000b222.bin
8fac8c9e75e0b86caa6b9970f61cd6d821d8688bcc195e7d2e5d7aea30016475
pdf-font-stream PDF embedded font (sfnt) at offset 0xB222 14600 bytes
font_01_sfnt_off0000d6d3.bin
b73d8cef2c4166326c296f9aff52952303210502f3dc588eb31666ced0836ccf
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6D3 10680 bytes
font_02_sfnt_off0000ef23.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF23 16792 bytes