Malicious PDF — malware analysis report

Static analysis result for SHA-256 07c2c370abec6d7f…

MALICIOUS

PDF

78.0 KB Created: 2021-09-08 16:05:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c1d2d997877111afd5c2c881c9683709 SHA-1: 6f5d0a7518476f997b7474e88ced4a293211be11 SHA-256: 07c2c370abec6d7f4270eeaa1dcabdcadb721752761c1d0a67c6dfade0b19105
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF was flagged by multiple heuristics as a link farm, with several URLs pointing to compromised WordPress upload storage and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking readable content but containing numerous embedded URLs that likely lead to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://minhvuongthuphap.com/upload/ck/files/40807128100.pdf In PDF document text
    • http://ros.by/ckfinder/userfiles/files/75099837362.pdfIn PDF document text
    • https://multimetrics.com/ckfinder/userfiles/files/38219053173.pdfIn PDF document text
    • http://mirutte.com/newsfiles/files/nobaruwosurepitojifegop.pdfIn PDF document text
    • http://mynotary.ca/sites/all/sites/mynotary.ca/files/merilujupugowutasewe.pdfIn PDF document text
    • https://ou-ravda.com/ckfinder/userfiles/files/15883507420.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109071850278123.pdfIn PDF document text
    • http://satisfytech.com/ck/upload/files/19255334647.pdfIn PDF document text
    • http://getsolarny.com/userfiles/file/defafomevirevuzekakijix.pdfIn PDF document text
    • http://hstechno.com/userData/ebizro_board/file/xivez.pdfIn PDF document text
    • https://simbhaolipower.com/images/file/muwina.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161366c4917443---43068696716.pdfIn PDF document text
    • http://mtcnx.com/upload/fckimagesfile/48270136210.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/gosilexudesuku.pdfIn PDF document text
    • https://mimpiindah2.com/contents/files/xeduvikotetaxet.pdfIn PDF document text
    • http://nenkin-t.com/upload_img/ck/files/21026533216.pdfIn PDF document text
    • http://jia-longsofa.com/uploadpic/jialong151126/files/202109050105511377.pdfIn PDF document text
    • https://carolinevlieghe.fr/images/file/76824026676.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9d81f3c3d---87535450761.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/bad768263452b8e10721585414913808/komogizun.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/10125401733.pdfIn PDF document text
    • http://drumlockingclamp.com/FCK_Editor_Images/files/28082035817.pdfIn PDF document text
    • https://ssmavidiyar.com/public/content-images/files/71385580046.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=factorising+quadratic+expressions+worksheetPDF 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_off0000c9c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e1dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1DC 11248 bytes
SHA-256: cb4e4e1046338c9d9b21f676be910768955520c7ec68b618955a7e7e5a155f8b
font_02_sfnt_off0000fbc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBC4 17836 bytes
SHA-256: cf633384d167995fe784e1ae75a0be052871df0f8a1064533ee23af872bbaa51