Malicious PDF — malware analysis report

Static analysis result for SHA-256 c850ac75e231b7d6…

MALICIOUS

PDF

84.4 KB Created: 2021-09-03 15:05:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 16c64531258bfe622c7976d928f5288f SHA-1: 58052dc82a9784ebbba44605099b831e131b1c26 SHA-256: c850ac75e231b7d6bdd7bdade008b6eb97846c50d6804331115f696f538274b9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. The document body is heavily truncated and unreadable, preventing a more specific analysis of its lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://eternoohydro.com/d/files/43974390012.pdf In PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b35eada584e---vogatelule.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/kt4kcrdvj2be52hu73j27ss3g5/66835092843.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/15268959973.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2e79d4b9ab---57108755599.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/i9m82bggdsgep8r2u4ak8uh4bu/merixo.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/jtasul6sn4rf93c6gjqorshb4l/wapasiwofupadi.pdfIn PDF document text
    • http://ky-auto.com/uploadfile/files/xamifisozozuvetutaxoxed.pdfIn PDF document text
    • http://lighthouse-connection.at/myPix/file/kemusekuzatipu.pdfIn PDF document text
    • http://zhouzhuanx.com/v15/Upload/file/20218101424105177.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/pewawarapa.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/91590245404.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/guxamafijukuxatopunilonar.pdfIn PDF document text
    • http://coomargroup.com/ckfinder/userfiles/files/88374206152.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0dbc7beb5061c4f1799da8c8ce91434a/bikorix.pdfIn PDF document text
    • https://bawwabatrizq.com/userfiles/file/64874451032.pdfIn PDF document text
    • http://www.odnpoznan.pl/fotki/file/file/57245190795.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/gcvo5a9s45bmmv51128ihtrbd4/55782795169.pdfIn PDF document text
    • https://imihwa.com/uploads/image/20210819/files/20210819133542.pdfIn PDF document text
    • http://linklandhotels.com/upfile/editor/files/19858407253.pdfIn PDF document text
    • http://ecohouse-lab.com/userfiles/file/fukoregoneramubofejazur.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/o2klknrf9kvro065hqjhclt93t/19398450809.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d0949b00a06---3041891191.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/86f6d533fcdbf6eb2aafe4f082072aa8/murosuzidavikus.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/c78a266e8ba00a1a1cbdbbd34450e6bf/33019405057.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e3f690349d---21107245075.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/161101d00a2e5d---zofibalifixupulisi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=legal+metrology+packaged+commodities+rules+2011+pdfPDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/475b82ae8a1f5b685f5617d3c9ebf75d/fexubofesupakeforazaru.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_off0000e40d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40D 17188 bytes
SHA-256: 4910e97887cdb20ae8e026974b36b96f4ec7cb30ab78c2ddd988325726eed619
font_01_sfnt_off0001105c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1105C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012873.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12873 11416 bytes
SHA-256: 1a36a416fee878958de1d911a6eb6981d871fe1aa8998ed2df77325a21c5ad5d