Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d5de9075e8e3f83…

MALICIOUS

PDF

81.8 KB Created: 2021-09-16 14:43:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cda8f8518e4aee78985623ad1ccdec9d SHA-1: d6620b3fe2e3851fe3f87693c4466a78fb40969f SHA-256: 8d5de9075e8e3f8369c04f0373d9c16a5bd3f2bb54e0ce36a274b7fb9626d785
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The heuristic analysis revealed the document functions as a link farm with numerous embedded URLs pointing to various domains, suggesting an attempt to redirect users to potentially malicious sites. While no scripts were directly extracted, the nature of the link farm and the detection names point towards phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1613661316346a---38665605712.pdf In PDF document text
    • http://theartofdesign.nl/ckfinder/userfiles/files/pejisutu.pdfIn PDF document text
    • http://gitishahjahanpur.org/ckfinder/userfiles/files/dugavigugebegafogudujof.pdfIn PDF document text
    • http://kamnitikamini.si/upload/files/lenuxaguxub.pdfIn PDF document text
    • https://uudanbury.life/files/file/vomibavofotavazafodabo.pdfIn PDF document text
    • https://chv.vn/userfiles/file/vixazifutaraziber.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/saperasovovekusanajoji.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/xuxoduturetim.pdfIn PDF document text
    • http://ilovehikari.com/uploads/files/disaruxobuluwupesenavo.pdfIn PDF document text
    • http://stagegator.scorchmark.com/stagegator/ckfinder/userfiles/files/36184561866.pdfIn PDF document text
    • http://banquat.com/userfiles/files/jarararufatevagogivuna.pdfIn PDF document text
    • http://dpsszczytno.pl/photo/file/sijub.pdfIn PDF document text
    • https://bdata.vn/upload/files/95247202012.pdfIn PDF document text
    • http://thestarbusan.net/FileData/ckfinder/files/20210912_B01333F3326DA2EE.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/e588d149a8020e5d43d9a25c3d9fb59b/52033055862.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/budakanifurepojiz.pdfIn PDF document text
    • http://bacsiha.com/public/ckfinder/userfiles/files/napogawijune.pdfIn PDF document text
    • http://mrcubezpieczenia.pl/app/webroot/media/files/61758237235.pdfIn PDF document text
    • http://goodlack.cz/userfiles/file/nozetiludoni.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161305c80e6c11---wosabaruxojoraru.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/69415973266.pdfIn PDF document text
    • http://kunbot.com/upload/files/wezemifuzawepof.pdfIn PDF document text
    • http://duythuc-bearing.vn/uploads/userfiles/file/bekivikisuliwukuganepobiz.pdfIn PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/xidofezutovolanupivigogaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=lollipop+5.1+updatePDF 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_off0000d5ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5EA 10320 bytes
SHA-256: 21972a09e31a2e8343ed8b809f837bfd636e05f4c63372190ac23b1bf6606012
font_01_sfnt_off0000ed60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010572.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10572 20096 bytes
SHA-256: c9d79653d476c8bac60cfe32b226ece4e330f3536573131ce09b0f3047ad4149