Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3c8aae7cd8aeb91…

MALICIOUS

PDF

81.0 KB Created: 2021-09-23 23:46:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4ff13ddd45978a3adab0972160054a6b SHA-1: cc60a00bd75b54a0853a092709053037279d3f30 SHA-256: e3c8aae7cd8aeb918f9032935606f790b8ea906be1fcc2127d98af57bf9d17c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and ML classifiers indicated a high probability of maliciousness. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The primary function seems to be acting as a link farm, likely to redirect users to malicious sites for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://allytemp.ru/uplcv?utm_term=k+means+clustering+color+segmentation PDF link annotation
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/90514912489.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/5565621453.pdfIn PDF document text
    • http://handlpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/60890398412.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1614b2f19b9c7b---xutenivugipanujeposutogo.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/litamubusibobunuduxenuwe.pdfIn PDF document text
    • http://itcbeautytrainingschool.com/userfiles/file/59509964495.pdfIn PDF document text
    • http://ndfeef.com/radiant/mechimobiles/userfiles/files/xexaxi.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/rikovilenilipifosa.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/22529627625.pdfIn PDF document text
    • http://e-cluny.cz/UserFiles/file/kigapidadasasu.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/161416d1c4d0c3---nugibevoko.pdfIn PDF document text
    • http://toonesk.com/upload/15893062105.pdfIn PDF document text
    • http://germainelecocq.it/userfiles/files/zegasejudujofixu.pdfIn PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kawizafi.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/ckfinder/userfiles/files/lepupisudejusoxer.pdfIn PDF document text
    • http://muszempilla.com/files/file/podinesidagopuzor.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/80831224622.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/toporipixi.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614982fd7d884---womimuduf.pdfIn PDF document text
    • http://tischlerei-schlusche.de/sites/default/files/file/28993843906.pdfIn PDF document text
    • http://dighakanchaninternational.com/FCKeditor/file/febazedavegirenise.pdfIn PDF document text
    • http://3e-recycling.ru/app/webroot/filesfiles/fosunoledewadulux.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_off0000d837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD837 17304 bytes
SHA-256: 1320c92cc0e7e898ae4eaf41daf756966a76232d4b3a25af030bf106d15b5c26
font_01_sfnt_off000105b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC8 10664 bytes
SHA-256: c84afce10de8a76182d1dcdf2b97247d69938998735ee8da7bb11873eee2ab23