Malicious PDF — malware analysis report

Static analysis result for SHA-256 c99c92f6d24db2d9…

MALICIOUS

PDF

70.3 KB Created: 2021-09-22 18:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 65ca6fbc28b03fdbd9fa0222d22b436f SHA-1: f303dc7d0c866640276a3d19567df42b8461022f SHA-256: c99c92f6d24db2d97ff4b60d12bbf78ceded3370504d467ce9746bfc20243bb1
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing trojan. It contains numerous embedded URLs that form a link farm, directing users to potentially compromised websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates these links are hosted on disposable domains, a common tactic for distributing malware or conducting phishing campaigns. No scripts were extracted, but the presence of multiple external URIs suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6664

Heuristics 5

  • 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
  • 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://allytemp.ru/uplcv?utm_term=luna+vpn+android PDF link annotation
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/runolumawu.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613ccaaf2eec0---julor.pdfIn PDF document text
    • https://akconta.com/uploads/files/puvovabapukisugeli.pdfIn PDF document text
    • http://velocimapper.com/webfiles/file/31329927524.pdfIn PDF document text
    • http://www.otevrenysklep.cz/ckfinder/userfiles/files/kofigotezidim.pdfIn PDF document text
    • http://humanlitech.com/files/files/janezumiturojodotetijiri.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/6424844670.pdfIn PDF document text
    • https://nullemont.fr/nullemont/ckfinder/userfiles/files/93595584374.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/tusozenaw.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134fad86da7c---dakitubelowijewixetirag.pdfIn PDF document text
    • http://studio5r.com/userfiles/files/69407359636.pdfIn PDF document text
    • https://simpangkanan.com/contents/files/3222303531.pdfIn PDF document text
    • https://ventadeterrenosurbanos.com/userfiles/file/81900357223.pdfIn PDF document text
    • http://ceroki.com/image/files/59588913610.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/p92snadrov3fo2nqglviiiovap/71388726245.pdfIn PDF document text
    • http://xmzhj.com/UserFiles/file/subemorofetuse.pdfIn PDF document text
    • http://cmorshomecareassociates.org/uploaded_files/userfiles/files/47248727531.pdfIn PDF document text
    • http://familiegravesen.dk/userfiles/file/82543411762.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/26493228657.pdfIn PDF document text
    • https://igraonica.me/userfiles/file/gofepewetinixevesigejofu.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/mabigeviwam.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614020bdbae38---51030205315.pdfIn PDF document text
    • http://hanleyresources.com/images/38426666066.pdfIn PDF document text
    • http://wirtrauenuns.ch/images/file/65171884160.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d7d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D2 10064 bytes
SHA-256: 9f37d45c97b7e42531a852a1eba48b0c549ca67e678056d0b97bc6f8eafd6130
font_01_sfnt_off0000ee34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE34 18180 bytes
SHA-256: f1e2d6f4318ad9e3cfd6bce19f5136ddf0969ed77b4497095c4150f1d3538d7f