Malicious PDF — malware analysis report

Static analysis result for SHA-256 99d5fb9f8ffdfa48…

MALICIOUS

PDF

80.8 KB Created: 2021-09-22 09:13:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8bf6cb8b5cceb14385c559180347ed9f SHA-1: 0337a45e9a9b1fd1505c4280e3a56e629c7ea9c1 SHA-256: 99d5fb9f8ffdfa48939287f63741f2d97082b2080a422dcaa2ac207df4f86bc7
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The embedded URLs, while numerous, are primarily part of this link farm, with the most suspicious ones hosted on potentially compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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://vilocom.net/webroot/img/files/24500329427.pdf In PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132856eb737d---natupesegivebonubusini.pdfIn PDF document text
    • http://talesma.com/E/file/xozunupebatufuta.pdfIn PDF document text
    • https://webbsoil.com/home/webb/public_html/ckfinder/userfiles/files/migikuxajagetoveliwo.pdfIn PDF document text
    • http://geometrarontani.it/userfiles/files/xufazidisaduwizox.pdfIn PDF document text
    • http://bodemveenweiden.nl/bodem-veenweiden-img/5432060006.pdfIn PDF document text
    • http://compow.net/ckfinder/userfiles/files/zidatazodulafi.pdfIn PDF document text
    • http://studioassociatoemc.com/userfiles/files/kusezunowagagufukolo.pdfIn PDF document text
    • https://www.confirmedtour.com/files/67072469470.pdfIn PDF document text
    • http://huzatfokozo.hu/editor_up/dadunupikubi.pdfIn PDF document text
    • http://att-na.com/upload/42156167987.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/sumalujenilojogep.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1614ac949b49e4---79588135075.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/69781036864.pdfIn PDF document text
    • http://decentlogistics.pk/survey/userfiles/files/rupizorodipabam.pdfIn PDF document text
    • https://diphong.com/uploads/30916623346.pdfIn PDF document text
    • https://groupekineconcept.com/userfiles/file/69427126656.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/161368051c8bec---fimiwovopuvolose.pdfIn PDF document text
    • http://flightshop.jp/images/blog/file/67477712254.pdfIn PDF document text
    • http://immodraft.nrw/images/architekten_agentur_images_/file/tumavoviduvoderedozaduse.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/risatiwujotoxin.pdfIn PDF document text
    • https://sudhirsachdevaclasses.com/ci/userfiles/files/98859726159.pdfIn PDF document text
    • http://jujucuisine.com/userfiles/file/marolexanixajofate.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=dj+am+documentary+streamPDF link annotation
    • https://b2cdemo.tickets.com/content/files/67506410343.pdfIn PDF document text
    • 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_off0000d631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD631 10740 bytes
SHA-256: e6097c941c482a90df060c68b3f9dbb23daabcd1aa4be412a82c3f33fbfa609b
font_01_sfnt_off0000eee6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE6 18160 bytes
SHA-256: bbdc6571b8bf70ac2ead1db132cdd53b5217de42180f05e73adfc517372d9029
font_02_sfnt_off00011e04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1