Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bc92cec175513e9…

MALICIOUS

PDF

69.2 KB Created: 2021-10-04 07:28:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 7684133cee1d750d3647cdb6dda9e8c2 SHA-1: 82cdea29cb5f95c7ba810ace54dae63488fb24b9 SHA-256: 6bc92cec175513e955ed5a69127ede19d84157a28d90ef2031706ec31b0be342
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS upload storage and disposable hosting. Although no scripts were explicitly extracted, the PDF structure and link farm nature suggest it is designed to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/b576e80edee162234505a61ca2fdf19f/51614383979.pdf In PDF document text
    • http://kapfenberger-schuetzenverein.at/userfiles/file/65790284164.pdfIn PDF document text
    • https://5703n1n6999-6a55.com/contents/files/jekasiberirum.pdfIn PDF document text
    • https://www.utn.ac.cr/sites/default/files/files/gefewiminuvododirugem.pdfIn PDF document text
    • http://cornucopiafrederick.com/uploads/files/42580526216.pdfIn PDF document text
    • http://teewer.mn/ckfinder/userfiles/files/sejewatopirogobofedekulav.pdfIn PDF document text
    • http://www.vnos.vn/app/webroot/uploads/files/dorigikize.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/negikanagisaliromuzon.pdfIn PDF document text
    • https://hoavily.com/uploads/files/jowegagekakutakenu.pdfIn PDF document text
    • http://yugreat.com/filespath/files/20210914015308.pdfIn PDF document text
    • https://khachsan295doson.vn/namthuan/images/news/files/duroluzidasobil.pdfIn PDF document text
    • http://ondrejkocar.cz/img/file/tosiditedosaveg.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/39111672668.pdfIn PDF document text
    • http://chelseafoodmart.com/uploads/files/87591513558.pdfIn PDF document text
    • http://damutech.kz/upload/2021/09files/210918132038730374mjfo7.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/pesaliletusijuk.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/90956600370.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/70105375086.pdfIn PDF document text
    • http://wccflooring.com/userfiles/files/6880250490.pdfIn PDF document text
    • http://likebarcode.com/image/files/20210928_052214.pdfIn PDF document text
    • http://lnianemarzenie.pl/userfiles/file/12757167093.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba8b0c776c---48358922657.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/68539238797.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/md50354kako2o36nqrafet1js0/nabijebutumobewivabuni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=talking+tom+with+friendsPDF 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_off0000b032.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB032 10940 bytes
SHA-256: 08e1af5abe35f3001dfa44d9a7f862a2fed68689f9ffa1288d271197bf17b15f
font_01_sfnt_off0000c933.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC933 15192 bytes
SHA-256: 002448abf4f42553db803ad1ca06f0073f340a229e075cafbba63921d818d89a
font_02_sfnt_off0000ef9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF9A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1