Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd99bdc4da4706d9…

MALICIOUS

PDF

91.4 KB Created: 2021-09-23 08:35:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 75f0aecd83dddfffc8111c3a10bac6f7 SHA-1: 9a55daddb99f3fdb6f85e1649e6b407f70eb9114 SHA-256: fd99bdc4da4706d9854516ae3a296e34f52fc5fc2ec7df9ce2a71f4d20b449ae
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as containing a link farm pointing to compromised websites and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were extracted, the presence of numerous URLs, including one hosted on a compromised WordPress upload directory, suggests the document's primary purpose is to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://hanyuchina.com/upload/files/28324396741.pdf In PDF document text
    • http://3colorjazz.com/fckeditor/userfiles/image/tarozokedovamaduvolum.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/94dedm043s928jhjh40hqp7dva/zedigefevuxelakilova.pdfIn PDF document text
    • http://aibasylhet.edu.bd/app/webroot/ckfinder/userfiles/files/6167590787.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/xezabafopu.pdfIn PDF document text
    • http://sushi-belovo.ru/files/rakugijade.pdfIn PDF document text
    • https://peptidturkiye.com/ckfinder/userfiles/files/lijogatixigofoxoselez.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142b356472c2---ximajuvamajekilaxogadiga.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/7f71ca5eeeb70e3bfa465294c8e73218/limeratavekeripevabilok.pdfIn PDF document text
    • https://marjoyunlar.com/calisma2/files/uploads/8321783445.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/rewuloxazeroketo.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/73954635488.pdfIn PDF document text
    • http://freeski.hu/freeski/file/tugutelumepodewafibimis.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/81684267341.pdfIn PDF document text
    • http://cataga.de/beta/files/file/74827244413.pdfIn PDF document text
    • https://desco.scp.hr/files/takigawidorob.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/roxodigavabopapuxoleduve.pdfIn PDF document text
    • https://gosselindesign.com/images/from_fckeditor/fichiers/9535730210.pdfIn PDF document text
    • http://romanasulcikova.cz/userfiles/30615112911.pdfIn PDF document text
    • http://almawred-sy.com/files/adminfiles/files/vogat.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613719dd36214---votukisiwaregola.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/161448663ef672---59922034388.pdfIn PDF document text
    • http://checopharma.com/upload/files/2703889900.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/gelujomoke.pdfIn PDF document text
    • http://ksiclubbiz.ksiclub.org/svnprojects/DHD/Source/images/files/fuzax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=pascal+wager+apk+downloadPDF 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_off0000f799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF799 21196 bytes
SHA-256: 85ca5618c657e6533be86d3e9743a3037a6629bc33c362d8d91baa75a5db12e4
font_01_sfnt_off00012f40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F40 10680 bytes
SHA-256: f10b39be44fff53b88c633456139dd8cd162fa3e8a5085d6a8f3ea09c18c6884
font_02_sfnt_off000147c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1