Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc9f6a65b3283b7b…

MALICIOUS

PDF

84.7 KB Created: 2021-09-21 13:33:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 26997e51bb7a145b310d99ed1e54f376 SHA-1: 502042df4b4dd6780400899fb8fbd4bd0ecf091b SHA-256: dc9f6a65b3283b7b30d05f5f8dc087a33cebef5c2b47cea34614a90482a331be
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains a link farm pointing to numerous URLs, many hosted on compromised WordPress sites, suggesting an attempt to manipulate search engine results or distribute further malicious content. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16146c794aba5b---gefox.pdf In PDF document text
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210917093039.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/d8ec39710cfa09afa4cd7c7eae22b499/getugiwufajezujizelup.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/64f42ba1a633cc77a55851898c17ccc4/95014318619.pdfIn PDF document text
    • http://winteringlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/91824604828.pdfIn PDF document text
    • http://cncforginghammer.com/d/files/63889773910.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/98e9bf0755c547703b5c703919aed824/62004426021.pdfIn PDF document text
    • https://vnjhanoi.com/upload/files/kowijutubek.pdfIn PDF document text
    • https://yodishit.com/uploads/userfiles/file/27546128494.pdfIn PDF document text
    • http://rymwid-training.com/userfiles/file/7388278405.pdfIn PDF document text
    • http://soles2walk.com/data/file/40436168565.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/kujezopabimidu.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/supisumojulimuz.pdfIn PDF document text
    • http://bud-drog.pl/userfiles/file/pejesex.pdfIn PDF document text
    • http://yogasol.cz/ckfinder/userfiles/files/58760099731.pdfIn PDF document text
    • http://accapierre.it/userfiles/files/tomavawililivilimu.pdfIn PDF document text
    • http://jeyadhurgatemple.com/userfiles/file/xuzanoxogaposemi.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16147d72062c28---96506131710.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/62875922593.pdfIn PDF document text
    • http://kossuthdigisuli.hu/userfiles/file/8554945619.pdfIn PDF document text
    • http://chpcentre.com/files/file/54077015827.pdfIn PDF document text
    • http://kpdb.org/userfiles/files/vowefok.pdfIn PDF document text
    • http://otestmanager.com/club/data/userfiles/file/20210921005732.pdfIn PDF document text
    • https://axlthailand.com/imagexx/files/38472777819.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=firestick+free+moviesPDF 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://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_off0000e7ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10016 10320 bytes
SHA-256: aafe76dd2211d98219c0fdb9e102008c40e528a09b313d9d68127595e053598c
font_02_sfnt_off00011770.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11770 17760 bytes
SHA-256: 199cf470b67d208508fc34977c80abd8a8cfce388ae902c2908388618127a0d9