Malicious PDF — malware analysis report

Static analysis result for SHA-256 4309e5185a38c91c…

MALICIOUS

PDF

72.5 KB Created: 2021-09-26 02:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d6db4766b844a3fe1e5bf231a5815e09 SHA-1: b3c6179c67b4ad782c8638724c799a0f976a3882 SHA-256: 4309e5185a38c91c11f22fb814e879e47d76dc22625b4d9e47cd325ae12f5d8f
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://dioceseofniranam.org/userfiles/file/sadaxat.pdf
    • http://vevo.keresztessyoptika.hu/elemek/file/58484870423.pdf
    • http://funkyspa.net/ckfinder/userfiles/files/zozeb.pdf
    • http://xnucleus.com/members/member_images/files/30100025797.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a0cf94ca7e---gomaxaguzeboresowuvit.pdf
    • http://custom-mugs-factory.com/uploadfile/files/nupamejeb.pdf
    • https://hiroyoung.com/data/files/38440262039.pdf
    • https://kaxtongroup.com/home5/maxconne/public_html/kaxtongroup/assets/images/newspostimages/files/34558471592.pdf
    • http://nurugelexport.com/ckfinder/userfiles/files/19016137231.pdf
    • https://sabagdasarov.ru/upload/file/jegowupimenudimuxikixofu.pdf
    • http://przedszkolenisko.pl/userfiles/file/1302663098.pdf
    • https://aaaxxion.info/images/file/23323767507.pdf
    • https://www.mediawerf.nl/bundles/store24backoffice/ckfinder/userfiles/files/49677546085.pdf
    • https://instalacje-elektryczne.net/ckfinder/userfiles/files/mesovedasigifetef.pdf
    • http://koslita.eu/ckfinder/userfiles/files/vagidisejoweb.pdf
    • http://matsonconstruction.net/userfiles/file/21709103501.pdf
    • http://tea-ra.com/user_data/upload/save_image/files/nuvudikozafilu.pdf
    • http://ks-system.co.uk/ckfinder/userfiles/files/pojuredolovopudina.pdf
    • https://tefen67.com/userfiles/files/makesiniz.pdf
    • http://bilateralmatters.org/userfiles/file/77223828869.pdf
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/dd07516a60ab3af901c25f41f09a805b/47878205401.pdf
    • https://harteron.ee/userfiles/file/woledetabapuga.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3c185d640---jugurubuxadataniwod.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=headway+intermediate+5th+edition+workbook+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_off0000b5b9.bin
76304a00adedaf7cc9dc065dce50e0c4c30ef2620a100ca516c8c2e09536d316
pdf-font-stream PDF embedded font (sfnt) at offset 0xB5B9 11108 bytes
font_01_sfnt_off0000cf37.bin
b4f86ecc6307bc6d07dba654ff29921b1443ae9350e98178f8c5fecf1390c0bd
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF37 17604 bytes
font_02_sfnt_off0000fc0f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC0F 16792 bytes