Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9b9e52b3579e979…

MALICIOUS

PDF

70.1 KB Created: 2021-09-30 13:50:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c19bc9efcdf4c0f3f76eab16037a4f38 SHA-1: 016ef18fab8986dd61638e607f11216676b6773a SHA-256: c9b9e52b3579e979110953e02d6855ee84a58e1cf990282663bb88c53854be5f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm. The embedded URLs and the PDF structure suggest an attempt to redirect users to potentially malicious or scam websites, likely as part of a phishing campaign. No scripts were extracted, but the PDF's nature points towards social engineering to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://wastran.ru/uplcv?utm_term=words+their+way+free+pdf PDF link annotation
    • http://armanetti.com/images/32589379011.pdfIn PDF document text
    • http://bscsaoner.in/ckfinder/userfiles/files/61277452938.pdfIn PDF document text
    • http://hamdannepal.com/userfiles/file/pikeret.pdfIn PDF document text
    • http://wedooverseas.com/userfiles/file/nafabojurasoxevam.pdfIn PDF document text
    • http://fra2ange.it/userfiles/files/gonitimebutowanizozusi.pdfIn PDF document text
    • https://mountmoriahcamp.com/media/45771121556.pdfIn PDF document text
    • https://memo-log.com/userfiles/file/lawigokow.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/sogejisukezorukapo.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/junusesefokiwileba.pdfIn PDF document text
    • http://lapmaymn.samdigroup.vn/app/webroot/upload/files/36233328992.pdfIn PDF document text
    • https://brakos.it/file/manotekosamebinarotozave.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/43599921377.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/jovisawukexeritenasimofu.pdfIn PDF document text
    • http://ok-poland.com/userfiles/file/jutokodonuvoxesa.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/d75d7d634c2e40eb8e988742b5f88beb/kimujozerefobabisewas.pdfIn PDF document text
    • http://saraya-shop.ru/upload/files/bilugu.pdfIn PDF document text
    • https://suruburi.net/mm/file/85820472786.pdfIn PDF document text
    • http://doingthing.com/downloads/blog/geust/files/67178369681.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16147feb0bd243---46954865907.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161495a5f67055---36684163683.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/60033719842.pdfIn PDF document text
    • http://harnettcountyhba.com/userfiles/file/nitemovinekikore.pdfIn PDF document text
    • http://cwpni.com/userData/ebizro_board/file/zajapekoralolusot.pdfIn PDF document text
    • https://goldenlinejsc.com/userfiles/file/10084120299.pdfIn PDF document text
    • https://factorysales.com/userfiles/files/64675809537.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/32598479649.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/dusamodurananujoku.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_off0000b58e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB58E 10640 bytes
SHA-256: 28b1926f67c92416a5048e335831de5b0167acb2017d68e07ad13b5d174409c7
font_01_sfnt_off0000ce1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE1C 14496 bytes
SHA-256: 862537a86b8b0515b338f3b89c60b4fe2f87ed3e4db20a2d0e27ea0b0ed7f9b1
font_02_sfnt_off0000f232.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF232 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1