Malicious PDF — malware analysis report

Static analysis result for SHA-256 b887198791e7ce7c…

MALICIOUS

PDF

78.8 KB Created: 2021-09-15 13:44:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8216b175d50c086ad957f0e41ad81722 SHA-1: c0e9532393af37470a13f0818f89493745d11de9 SHA-256: b887198791e7ce7c19ee71318e964e373eaefe7647ec866fd677e47df5d1ff64
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 disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://irlanc.ru/uplcv?utm_term=descargar+musica+gratis+al+celular+android
    • http://xn--939a66v0zjo3bcvdmrp.com/data/ckfinder/files/befokadovibadediwobik.pdf
    • http://disonde.com/filespath/files/20210903141950.pdf
    • https://a-metal.e-giant.net/archive/file/files/pemavuso.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/pfe3397jvnh89ev6hij2h7g9cg/67689853834.pdf
    • https://ckmusicdesign.nl/userfiles/file/1817949390.pdf
    • https://pamukoglu.com/userfiles/file/1210246056.pdf
    • http://portableandcool.com/files/files/mavibifuwatolamo.pdf
    • http://magdrywall.com/project-new/christianbook/upload_images/file/xaxuzin.pdf
    • https://biocoils.com/img/file/9902160442.pdf
    • http://www.truca-taoules.com/ckfinder/userfiles/files/wevokewesemula.pdf
    • http://hoangminhceramics.com/app/webroot/uploads/files/25819941547.pdf
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/31436173000.pdf
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/31385b9f68eccb74bf4afa966cd9ee1a/nuliwigubeba.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e7ba94bf9---24331512218.pdf
    • http://mc-opony.pl/files/file/27274363157.pdf
    • http://ogledalata.bg/uploads/pages/files/xerexar.pdf
    • https://santaclara.com/wysiwygfiles/file/xixoxadadogivugozunupave.pdf
    • http://dges.in/userfiles/file/gexafiwemevomudirewoxovem.pdf
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210903223144.pdf
    • https://atcotourismtravel.com/userfiles/file/wulasulaf.pdf
    • https://eldorado777.ro/upload/editor/file/2811056369.pdf
    • http://munnartourism.com/uploads/file/74742670256.pdf
    • https://dodatkireklamowe.pl/web/uploads/files/xawivemugomanematis.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_off0000cefb.bin
70e193754fafd94a6a8bd8a38b2aaaea9da00cdd135efc39041a3598b9c655c1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEFB 10812 bytes
font_01_sfnt_off0000e7ba.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7BA 16792 bytes
font_02_sfnt_off0000ffcc.bin
1f856026a1cc7f5608a7aaa2fdea40e222f15216ace44e8c6186d027a62ca846
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCC 17996 bytes