Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5eac69a503d2f72…

MALICIOUS

PDF

73.5 KB Created: 2021-09-16 20:20:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a90d29f83be3e2a3a0cd34d8a59a6311 SHA-1: c1cf48a08f08cff09d8a5ebbd087207e1f4b9516 SHA-256: c5eac69a503d2f72f8ea3a04486ec29b88486f19685c79872f92c9ab929970cb
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL destinations strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://wastran.ru/uplcv?utm_term=what+method+you+should+override+to+use+android+menu+system
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/movuvamobuvimewelinek.pdf
    • https://gitedu.in/ckfinder/userfiles/files/bakudemalawoxala.pdf
    • https://vandolderskb.com/images/usr/51411112125.pdf
    • https://ocw.tw/uploads/files/65746174139.pdf
    • http://tsrmmessina.it/userfiles/files/zinavazufatolat.pdf
    • http://pension-erlkoenig.de/img/editor/file/piweja.pdf
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/5116bf8516069309abb8ff2735d9d1d6/47937504542.pdf
    • https://kenhquangcao.vn/uploads/files/majafuzenozo.pdf
    • http://morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135818368a49---10700789677.pdf
    • http://karlsbach.de/userfiles/files/89720597784.pdf
    • http://zoscm.zohukum.com/ckfinder/userfiles/files/13801147477.pdf
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/xonodi.pdf
    • https://aradmissions.com/ci/userfiles/files/7101367504.pdf
    • http://wpchkg.com/upload/image/file/20079037669.pdf
    • http://yksskj.com/ckfinder/userfiles/files/xaramixuwifem.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/161358e78d9c20---tiramigivujo.pdf
    • https://smlstripedbass.com/home/rock/public_html/ckfinder/userfiles/files/bimabigumun.pdf
    • http://alacartedesign.de/userfiles/file/marutigu.pdf
    • https://o-dance.com/upload/files/rawujowowimatagis.pdf
    • https://pnvvr.ro/userfiles/file/36945449864.pdf
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/40203517475.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/98ccde82fcec2eead89aed6c2aafc3ef/55772054155.pdf
    • https://ht-cooling-j3t.com/contents/files/fiwus.pdf
    • https://observatoire-omic.org/documents/file/29975787926.pdf
    • http://parkergeneralcontractors.net/userfiles/file/domesalajuxaludafufi.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_off0000bf80.bin
f1bb02bd3a0efb984b4000e4357796b639c589caa56adc7a01959cf115ab2414
pdf-font-stream PDF embedded font (sfnt) at offset 0xBF80 15376 bytes
font_01_sfnt_off0000e6cf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CF 16792 bytes
font_02_sfnt_off0000fee6.bin
ed687703ead84813d8c171322460eee4eb3bda587afa1369b43baebae336b6d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEE6 10788 bytes