Malicious PDF — malware analysis report

Static analysis result for SHA-256 b183fad05d6f518b…

MALICIOUS

PDF

79.3 KB Created: 2021-06-18 19:51:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: f4c979d71fb62a55cff727bfe187f7ce SHA-1: 500ce4b43d3606a957cbf0d989a5e8a38df8cf10 SHA-256: b183fad05d6f518ba601269fd684b1bb4c15b29b2a2f07319c9be4be8801d7de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to numerous distinct hosts, many of which are compromised WordPress sites or hosted on disposable domains. The document body, though heavily obfuscated, suggests a lure related to 'dotted lined paper pdf', likely a pretext to encourage clicks on the embedded malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://posekatzahradu.cz/files/file/12428442902.pdf In PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16097dfba4cb2c---99466107011.pdfIn PDF document text
    • http://goodwill.pl/userfiles/file/wegedatevixoxu.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/0kj9on9gkppbm7aujv64rgacs7/wumotudizegopa.pdfIn PDF document text
    • http://kingalbertltd.com/uploadedfiles/file/82924187734.pdfIn PDF document text
    • http://meta-min.com/files/kogezugikuxivevofevudar.pdfIn PDF document text
    • http://slsnn.ru/content/file/523967824.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/17041652243.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abb13762351---86991895495.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/rokesenoluxed.pdfIn PDF document text
    • https://akita-inu.lv/www/files/files/laponivodibusared.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16081f90de5d5c---jukidekamaditofan.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/88028553473.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16081800735726---32326279742.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/bff918a2fb4fdf90d97fe1d93cf7f79a/nozopirazol.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/dd9612f01580e41b1d2b86413db98c19/dusivogafikufinaj.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b253d54b8f---61924520956.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=dotted+lined+paper+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://scripts.sil.org/OFLIn 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_off0000e239.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE239 4856 bytes
SHA-256: 230198dae4ce48438ae575f6d89e0e6f931cf479d981ae48d0e1a0c2d4a531cc
font_01_sfnt_off0000f2d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D0 11272 bytes
SHA-256: 5d4191b2c955d51d271b1e3fc406d56a9bbe8e6ae8375ae2502d154233e0bd08
font_02_sfnt_off00011994.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11994 16204 bytes
SHA-256: e93acd332f5893643511f4cefd38969ad5c744ad1b08842a788b6be7d277dd15