Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5a96618389a9cd1…

MALICIOUS

PDF

78.6 KB Created: 2021-09-12 14:54:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3aa01c6444a10b5107fbf45e7cc3d140 SHA-1: 2eaf0c1b1efe1ee09f76173a81df4cb56577c69a SHA-256: b5a96618389a9cd1e1e43712a507d2545ac437230224024ebfdb9fd4f4244336
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, a common tactic for phishing or distributing malware. Several heuristics indicate the presence of these link farms, with some pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://inwebjor.ru/uplcv?utm_term=insta+saver+apk+pro PDF link annotation
    • http://kccmaul.com/files/files/xabevuv.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/sabinemupadevivi.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/64af59e8226b4f2f7036370aa114cbe2/boxokemogetoza.pdfIn PDF document text
    • https://smartcirclegroup.com/userfiles/file/57672250406.pdfIn PDF document text
    • http://carzip.biz/files/uploads/files/wuponurobezimoxif.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/3058479230.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/batelar.pdfIn PDF document text
    • https://terlickodds.cz/www/www/fckphotos/file/mejarep.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/narigofuzij.pdfIn PDF document text
    • http://www.golfusa.be/userfiles/files/nisoxevupupogi.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/161315c9dcd88d---52164273491.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133fd04efb79---66322570103.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/71825601673.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/vifituwetafiw.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/43501102973.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cfa37af15a---kikaderowewage.pdfIn PDF document text
    • http://www.jokilaaksonratsastajat.fi/file/26948708750.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/71210056012.pdfIn PDF document text
    • http://mvdeastudio.it/userfiles/files/zavotatetugijesa.pdfIn PDF document text
    • http://maybaobidinhdinh.com/upload/files/surejadagumapujon.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_off0000cea7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEA7 10216 bytes
SHA-256: 24868053423db44dee11d8bc458f15b332da7959c13afbf911679a975957e103
font_01_sfnt_off0000e5c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C0 17908 bytes
SHA-256: d4960394491d8e029d5f1654b3d3ac3af5482893730254f3a4e8e2fc5cd75b33
font_02_sfnt_off000114e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1