Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b3850dddcc70e14…

MALICIOUS

PDF

68.7 KB Created: 2021-09-28 00:47:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2e91ada9709271706b118067c984def1 SHA-1: d64879afd7f3beccb1db429a5ad15341fc5a9df1 SHA-256: 2b3850dddcc70e1431206ad2aa5116ace086c86cabb8af636f941dbbf90ec295
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of numerous unknown URLs indicates a broad distribution effort, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/dd3f4e7a076ab20c9295a483beb6acd4/jexodiwerega.pdf In PDF document text
    • http://thephinhmienbac.com/upload/files/darefowiw.pdfIn PDF document text
    • http://france-ex.com/images/blog/file/89362465692.pdfIn PDF document text
    • http://mitcostruttori.it/userfiles/files/samud.pdfIn PDF document text
    • http://syekp.gr/sites/default/files/file/nijuti.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16132d858542bf---96130451958.pdfIn PDF document text
    • http://sk4education.com/ckfinder/userfiles/files/nulexeruze.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/84199770377.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/32298895558.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7b67cb517---58980344191.pdfIn PDF document text
    • http://hugslock.com/app/webroot/img/files/gikusubusimutep.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b72d14f9ce---94593881035.pdfIn PDF document text
    • https://k85shj16h-561lt.com/contents/files/22987658131.pdfIn PDF document text
    • https://cingenito.ca/upload/editor/file/dewef.pdfIn PDF document text
    • https://embassyinvietnam.com/webroot/img/files/rabef.pdfIn PDF document text
    • http://woodwork.pl/ubezpiecz/obrazy/file/vutamuruku.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/24391305509.pdfIn PDF document text
    • https://landtop.com/filespath/files/20210916200318.pdfIn PDF document text
    • https://xn--23-6kci4asohe8k.xn--p1ai/userfiles/file/4227692093.pdfIn PDF document text
    • http://trunglam.vn/uploads/userfiles/file/7298896032.pdfIn PDF document text
    • https://ijestr.com/ckfinder/userfiles/files/pozovabekaxiba.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/22838612567.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/jabibuluzo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=sentry+mba+apkPDF 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_off0000b0a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8B9 10408 bytes
SHA-256: 89f50205dcf6a44bb09a92a11ef3cfd149638fc08e111a23dbd7c3146503795e
font_02_sfnt_off0000e01f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE01F 14840 bytes
SHA-256: cce3ff7d99c691fb00ca3f60e0febd0639cc2ece5cfb4df1c2403769b316ec2d