Malicious PDF — malware analysis report

Static analysis result for SHA-256 38071e8323958c25…

MALICIOUS

PDF

80.8 KB Created: 2021-09-09 02:17:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f6f1d10e6f5136d7de5b99fe450852ca SHA-1: 276025277230edfb72476eb84faf59c500354823 SHA-256: 38071e8323958c25db6cb2671cc96355a595452b7aff3d0600c1699782b91dd3
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to external resources, many hosted on disposable domains, suggesting a link farm designed to distribute malware. The 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristics indicate a high likelihood of malicious intent. The ClamAV detection and ML classifier further support the malicious verdict, pointing towards a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://wastran.ru/uplcv?utm_term=ps4+games+download+free+for+android PDF link annotation
    • http://www.hzkontejnery.cz/ckfinder/userfiles/files/50094222288.pdfIn PDF document text
    • https://falconshipping-uae.com/userfiles/files/98553228669.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/52543240208.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/fizatakiravapekade.pdfIn PDF document text
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/sagebulekoremapikaw.pdfIn PDF document text
    • http://studiotecnicodavico.eu/userfiles/files/dufupejipesagiguj.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161329fa66f7c1---71864870709.pdfIn PDF document text
    • http://csc0851.com/userfiles/file/20210908185415_4tga68.pdfIn PDF document text
    • http://iacsglobal.iacsinfo.org/content/uploads/files/82027557784.pdfIn PDF document text
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/76008867781.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/matuvinexevebokakakamom.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/14919199114.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/kafojubigawizemavi.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/wafasu.pdfIn PDF document text
    • https://muacash.com/webroot/img/files/xukumakesapijimu.pdfIn PDF document text
    • http://applexin.com/ttpsea/files/file/27765857277.pdfIn PDF document text
    • http://surestegc.org/documentos/file/xedubimod.pdfIn PDF document text
    • https://bankubezpieczen.pl/userfiles/file/31331887876.pdfIn PDF document text
    • http://clarksville.net/wysiwygfiles/file/35265919861.pdfIn PDF document text
    • https://bi-kiesabbau.de/cmsimple/images/file/6231661356.pdfIn PDF document text
    • http://silver.jo/ckfinder/blanc/files/65123434587.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/70035009362.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/65928059053.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/kowomufal.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_off0000d846.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD846 17236 bytes
SHA-256: 8180d7edd4f95d15e86a0d8735c3dc62268f948098d155f9465a44a70eda8c89
font_01_sfnt_off000104dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104DD 10764 bytes
SHA-256: 1dd78f5f2519c298be8e7ffc3d57466c83efd8b01af8253001737a9d28feca48
font_02_sfnt_off00011d7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D7A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1