Malicious PDF — malware analysis report

Static analysis result for SHA-256 55c5f14810070946…

MALICIOUS

PDF

81.6 KB Created: 2021-09-07 20:20:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8a65ff7d96e07a93102a51b38b8fd21d SHA-1: 52baea316442b5a8a587139bf08484ba98407b14 SHA-256: 55c5f1481007094672846efd30d4a52d95662b1763ad4787cff03d0f2dc884de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the PDF's primary purpose is to host a large number of links, potentially to lure victims to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://villkasz.hu/editor_up/47870012164.pdf In PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/virivuzifukiri.pdfIn PDF document text
    • http://carefirstwalkathon.com/clients/8/89/89514deb4c0e8807eb046cac28c4977f/File/69712729557.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a2012661704---76234128220.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/vabonitezewesutevowateb.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160fd349519abf---35101608427.pdfIn PDF document text
    • http://northphoenixmustangs66.com/clients/4/4b/4b49b54eec06ebba3741256e9f3e6f2b/File/nanon.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607523d608b5d---lamafi.pdfIn PDF document text
    • http://limoride.net/gallery/file/96778994612.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/62377520815.pdfIn PDF document text
    • https://atrax.hr/files/finedibivofafevelenal.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/xebuwokozabobaxina.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16085b82017f4f---14465449250.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/5135e751deb7973149d17e1603bdf0ef/bizesoravejerutodiboj.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2d0c00457---42156673542.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/46533864573.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a160a543306---63593833912.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/3763999913.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ed3a9ffc7---87891136142.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a592d2cce44---29139161655.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a088960d18c---98421473042.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607d27e4378d1---boxemutumimawe.pdfIn PDF document text
    • http://akvari-um.ru/userfiles/file/wubufusajugiworemapob.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=types+of+customers+internal+and+external+pdfPDF 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_off0000dbdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBDB 11060 bytes
SHA-256: c2b393c5d633220216e9b6a964f49734f10f62754ae564082a1f7bc48b6aab4c
font_01_sfnt_off0000f5a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A5 16868 bytes
SHA-256: 1ec47209967068ebbbe15e75811690edf4ad332d695debad57b283407a0b40c0
font_02_sfnt_off0001208c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1208C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1