Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c836ebc94415ef3…

MALICIOUS

PDF

80.0 KB Created: 2021-08-19 10:34:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1657d89f385c6c512a711fb153ad51d6 SHA-1: a70d7c2399e953d618ca61dfed434837a45dcf8e SHA-256: 8c836ebc94415ef3dcac0be05f051ef779f83e46f3e0981b29e6eddeb9dd562d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the PDF structure strongly suggest it's used as a lure, likely for phishing or to download further malicious content.

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://infrive.ru/uplcv?utm_term=bilderberg+group+daniel+estulin+pdf
    • http://rheinmotel.com/userfiles/file/zuzuj.pdf
    • http://sanarina.de/ckfinder/userfiles/files/63027888753.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/1b0d25a0ef41fbb6a65f045ede35bfde/gaxidefirepozolelupepum.pdf
    • http://www.hangmandigital.com/files/file/7875746157.pdf
    • https://footballsod.com/images/ck-uploads/files/bikejosipasupudoti.pdf
    • http://aj-logistics.com/stock/userfiles/file/20940983942.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/bcdc2bec5755404395a0a6c0c2c660ee/zawon.pdf
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160714e6945efb---logenakunupobez.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af8b998d6f1---53254895875.pdf
    • http://carriewoodfamily.com/clients/5/5b/5b9f2fb360c4065436fb7fe1267c3612/File/nusutibatepagirogitopuno.pdf
    • https://lesartsdansmonjardin.com/userfiles/file/20210717065131.pdf
    • http://mamnonhieutrung.edu.vn/ckfinder/userfiles/files/farafanixapupive.pdf
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160928c4c9da14---48219068444.pdf
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/ca6488616f969e4de36bedff825fa168/57524739488.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160ce7bd75fa49---53268056302.pdf
    • https://patoman.ro/ckfinder/userfiles/files/ropodazejutemoxevudalamek.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb75506bb09---90288559117.pdf
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bf45d536150---mepomusef.pdf
    • http://toroisg.com/public/images/files/nemegafisev.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f990770fbb0---52889780595.pdf
    • http://happy-travel089.com/CKEdit/upload/files/xulipirisoxutuguwin.pdf
    • http://www.prieteniitehnicii.ro/documente/file/pokovof.pdf
    • https://daynexweb.com/upload/ckfinder/files/mepanekaxegemiratuvemu.pdf
    • http://pcwenhua.com/uploadimg/file/16257036841603950758.pdf
    • http://chamdure.com/DATA/files/rozododanuxosawewagarubis.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d463.bin
298a4c9e35a701c05dfcf31cd3fc3774a550d774b7b0906b51adb123a741f79c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD463 16832 bytes
font_01_sfnt_off00010092.bin
d5b4080653b94fae9ef8749d6e75bd3a53405a6fdc6ec2a953dfa1ee6ff81f3e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10092 10968 bytes
font_02_sfnt_off000119b1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x119B1 16792 bytes