Malicious PDF — malware analysis report

Static analysis result for SHA-256 a98ac8abdef53499…

MALICIOUS

PDF

104.6 KB Created: 2021-08-11 10:48:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 55b373a94813ba9a01ecc0127b0d2810 SHA-1: 6fd6aa0fdebe1b9210f084ca9a96172d0309fca4 SHA-256: a98ac8abdef534994196859cfab3dd84e522cbc63bc1ff5ea6872549d63154ae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a phishing lure, employing a link farm strategy to redirect users to various external sites. Several URLs point to compromised WordPress uploads and disposable hosting, increasing the likelihood of malicious redirection. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/c44c7e6af2e82626bc01a46fa3ffa1ae/55820822148.pdf In PDF document text
    • http://yao-cheng.com/uploadfiles/20210703190836.pdfIn PDF document text
    • http://24cvety.ru/upload/files/4454295609.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/funiguzajexopadigaxafad.pdfIn PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/tjjg6tgsm0ei13gfs740d2oqu4/34805583215.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608b0c8ac97f3---fetiwun.pdfIn PDF document text
    • http://cloverdiamond.com/file/84250993544.pdfIn PDF document text
    • http://wrhs1967.org/clients/6/61/617565fc8afb9cc6d18abf932d248b7a/File/ruduzanefe.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160a4098b5f7fe---84972506003.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/2527c08e8fafeab1868112dec0cbeeab/tomelux.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c5906fd7a5a---12507350901.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160adb68e4f1aa---97525048575.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3a6d5cc55---veruloresemalaxu.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d01e95debf---78956662743.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/18367467569.pdfIn PDF document text
    • http://mamaskitchenorder.com/uploads/files/xepajoluwuzudusoko.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609a72a0198a8---vebugagegadokibokapoluxa.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/hdk7vk3b1f7fuuniboghu4eej5/vapivofored.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/48774356144.pdfIn PDF document text
    • http://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/40732212422.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/kejanuzadimetesabonuwot.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160735f47794c3---zapirelazuxoguvulakol.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba984f12d10---kexujaxuguxedelun.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160757e552929f---30020581586.pdfIn PDF document text
    • http://fitviewer.de/files/file/46772747763.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=sense+and+sensibility+2008+free+online+moviePDF 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_off000134ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00014cbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14CBF 16792 bytes
SHA-256: 30694988c27e824e323878654a0379e10afd95876ce2ebc0469dd1abbee38567
font_02_sfnt_off0001789d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1789D 11360 bytes
SHA-256: 72c32dff019b0092c7827c710ba5e79fb3be33762a4fd6b73360b992f9ad842e