Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef1adb486891d63c…

MALICIOUS

PDF

84.6 KB Created: 2021-09-01 04:21:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c2c26d5cf27d32e90c091baf43d02802 SHA-1: 7dd148f9f6a4222f945d536b8ccd4117de99f852 SHA-256: ef1adb486891d63c1c7b46e85a503c411742e607990efe4b40b99ebd8d46b198
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple external links and the nature of the hosting domains point towards a tactic of obscuring the ultimate destination and potentially leveraging SEO poisoning.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://gillsandgeckos.com/userfiles/file/46220200709.pdf In PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/3854e2efc7def1da3303cb95c59ee2b3/rubek.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/52058182375.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/29860472685.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093ceaa21e70---98229031587.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16090f10e3adcd---67577179745.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/63788a010870fb7eab00cae3afb47e7e/kubukitagojabojete.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16089fa1e7068f---monififopafa.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/072359a4439b52bb8109c9ec9ef2c6c9/pomisozijos.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad7ec97a8c3---57276930914.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16079ab0fb3eea---rikisomaxaxaza.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607844d16ab66---75923643262.pdfIn PDF document text
    • http://sure2trips.com/bot/ckfinder/uf/files/pigujiloninaxolalekawoke.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c503cc7cea9---gagibe.pdfIn PDF document text
    • http://rcp-ranstadt.us/files/rerufelodutu.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16099bdfe29f22---39564275166.pdfIn PDF document text
    • http://www.iece.in/userfiles/file/1950247372.pdfIn PDF document text
    • http://vagtteam.com/userfiles/Files/xewaferenowibaxik.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/c76u321dqb866f1m60pqu7f1fk/fejekunituxovuzud.pdfIn PDF document text
    • http://ewtch.com/upload/files/lusoviwaxagovijafipoko.pdfIn PDF document text
    • http://pokemom2.com/uploads/files/38625031862.pdfIn PDF document text
    • http://unsersohn.ch/images/file/24656540281.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/ppg9snadbr4a3p9gfc60ifjtr7/nojefunivu.pdfIn PDF document text
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/daravixelavu.pdfIn PDF document text
    • http://jucal.es/images/file/tajezaguzevigo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=anne+hathaway+singing+i+dreamed+a+dreamPDF 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_off0000e54e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE54E 10712 bytes
SHA-256: 871b79846a93e7b2a7119306891a6a89be9667ce5b1424c34a486c1b99fb2dfc
font_01_sfnt_off0000fd99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD99 17900 bytes
SHA-256: 62695d3555fb1f9ca3e2db7e9a85081d5712ffee5325fdd0f7dfe5cd5737bcf9
font_02_sfnt_off00012bfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BFE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1