Malicious PDF — malware analysis report

Static analysis result for SHA-256 c75cf36d7d9cc9df…

MALICIOUS

PDF

70.6 KB Created: 2021-09-20 23:10:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 70aecc291be15d491d8d208a3a4ac85a SHA-1: 5003de6f77ebd4534f55f7925ac05f0102faa009 SHA-256: c75cf36d7d9cc9df443f9d4fa06377e89f835b770508c8e2fded3493a21496ec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farm heuristics, indicating its primary purpose is to redirect users to external sites. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' and ML classification strongly suggests malicious intent, likely related to phishing or hosting further malicious content. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure points to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laborke.ru/uplcv?utm_term=textbook+of+anatomy+and+physiology+for+nurses+ashalatha+pdf+free+download PDF link annotation
    • http://teplo76.ru/uploads/file/sipizexonazeser.pdfIn PDF document text
    • http://architettoangeli.it/userfiles/files/52230049698.pdfIn PDF document text
    • http://rayocazar.com/images/elfinder-1.1/files/file/tadevusipemisisikimal.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/wumelemotoga.pdfIn PDF document text
    • https://loffoxfitness.mvwebsolution.com/userfiles/files/21701185850.pdfIn PDF document text
    • https://fivetc.vn/uploads/files/50222797102.pdfIn PDF document text
    • http://indigobaby.eu/upload/files/pulapizaxul.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/52378656253.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/86737512595.pdfIn PDF document text
    • https://coonvalleycc.com/userfiles/file/jiligukizevafoxijif.pdfIn PDF document text
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1614068a37a4d0---46523122445.pdfIn PDF document text
    • https://clove7.com/userfiles/file/gugonigexiponof.pdfIn PDF document text
    • https://abbma.in/admin/uploads/file/59381161519.pdfIn PDF document text
    • https://lesura.net/userfiles/file/jijuxefufinime.pdfIn PDF document text
    • http://c-amc.com/upload/files/vafasaxenop.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/a0b0aed156fa9f4dd0015264e30a1dd9/72793299149.pdfIn PDF document text
    • https://obermeyer-modemarkt.de/upload/file/wogoni.pdfIn PDF document text
    • http://royalrep.com/userfiles/files/menidini.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141a0bd47a2d---teruninuvoxujagazava.pdfIn PDF document text
    • https://bluetact.com/ckfinder/userfiles/files/rukuzamuxat.pdfIn PDF document text
    • http://ms-krmelin.cz/app/webroot/files/files/merepitux.pdfIn PDF document text
    • http://marine-inox.com/i/File/97406237493.pdfIn PDF document text
    • http://scarpatti.com/files/4224975377.pdfIn PDF document text
    • http://twtime.com/uploads/files/202109090744201466.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_off0000b379.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB379 11544 bytes
SHA-256: b66da33993082549a978ed443de98d60db4ad57a6f659300aa8d32a589330fff
font_01_sfnt_off0000ce51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE51 14832 bytes
SHA-256: b176e3a1dcc0e47f31ba962b0460df33395d20b188656f3ba7cbf11959453fee
font_02_sfnt_off0000f38e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF38E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1