Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c99085804b7bb10…

MALICIOUS

PDF

82.2 KB Created: 2021-09-12 03:46:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 39a7b103e63ace5d04aa625b088dd2c5 SHA-1: 9177f5c4a12638231052115a5c31f98b0e2e8647 SHA-256: 3c99085804b7bb10508ff9a23a244801270e6aef84ca88c931265b1fd7433976
156 Risk Score

Malware Insights

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

The file is a PDF that contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/e7821b4f6e09942443d62e7cb2e4e26a/damizititafurejodozenikot.pdf In PDF document text
    • http://www.emploi.nat.tn/ckeditor/ckfinder/userfiles/files/52499681563.pdfIn PDF document text
    • http://tokyo-sanritsu.com/userfiles/file/nupokezosaneboxawi.pdfIn PDF document text
    • http://pk.mo/userfiles/file/kabexawaputitewowerimet.pdfIn PDF document text
    • https://sunnyvale.com/wysiwygfiles/file/51830125588.pdfIn PDF document text
    • https://dehaventransportation.com/home/de/public_html/ckfinder/userfiles/files/93518779855.pdfIn PDF document text
    • https://bkairconditioner.cloud4demo.com/uploads/files/7123224686.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1613280af197bc---97166890781.pdfIn PDF document text
    • https://euro-m.si/web/dokumenti/file/sarenusulajaxojawi.pdfIn PDF document text
    • https://geloracinta.com/contents/files/dazomomusizoloni.pdfIn PDF document text
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/77515166037.pdfIn PDF document text
    • https://tramtron.vn/uploads/files/files/razus.pdfIn PDF document text
    • https://kaplaitalia.it/userfiles/files/39090094395.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/xobafobaf.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/xupotabujolelewerudugemes.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce0f494238---51498491621.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/wijepekixanuvatejopadonuv.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/pepelizamowalejodunizav.pdfIn PDF document text
    • https://apra.pl/files/file/83478401368.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/74605172858.pdfIn PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/vopufoxunugu.pdfIn PDF document text
    • http://clevio.biz/fckUpload/file/jolugul.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=play+music+from+sd+card+on+android+phonePDF 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_off0000ddc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC1 11000 bytes
SHA-256: 3de605c84cd01196c9ca6bc97e18446dbc391d01626e009ea57b7a9406d192d5
font_01_sfnt_off0000f720.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF720 16684 bytes
SHA-256: e259f3acf15baa5fc0d3e401ac7637a26c3c84d1a9e282a7786f4934edfa37e9
font_02_sfnt_off000122a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1