Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f856dc7d5be9fd4…

MALICIOUS

PDF

77.6 KB Created: 2021-09-22 12:08:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 64ee883d525380d826eeb7734104f317 SHA-1: bdc62a499a9d65d0fc3449c72459c130bd671ec0 SHA-256: 5f856dc7d5be9fd48b89db5b05d007515d9ff04e5decc036def56bf85e42cc1a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs, with one specifically linking to a download for 'pubg mobile lite official download'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a secondary payload or phishing content. The numerous disposable links suggest a link farm designed to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ketchas.ru/uplcv?utm_term=pubg+mobile+lite+official+download PDF link annotation
    • http://aarogyamedico.com/userfiles/file/4686478728.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/zusanarirebolirapaxo.pdfIn PDF document text
    • http://akiisushi.com/uploads/files/dujafet.pdfIn PDF document text
    • http://nanoservice.cz/upload/file/31438807486.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/86636976744.pdfIn PDF document text
    • http://dedanskecasinoer.dk/userfiles/file/19717076093.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/161404c20c4152---31087464050.pdfIn PDF document text
    • http://primethailand.com/ckfinder/userfiles/files/31064817842.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/40134565805.pdfIn PDF document text
    • http://thetestmag.com/userfiles/files/gebinogasukokubevimulowej.pdfIn PDF document text
    • https://weishinclinic.com/uploads/files/202109060707447257.pdfIn PDF document text
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/nosuxubele.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/vuwadisepano.pdfIn PDF document text
    • http://rund-sro.cz/UserFiles/File/sokerikibir.pdfIn PDF document text
    • http://taketty.xyz/js/ckfinder/userfiles/files/65916856599.pdfIn PDF document text
    • https://stancijanegrin.com/userfiles/file/5975103508.pdfIn PDF document text
    • http://mitroc.com/userfiles/file/welopesapagiwakapozenuk.pdfIn PDF document text
    • http://drsrkbedcollege.com/ckeditor/ckfinder/userfiles/files/3260840753.pdfIn PDF document text
    • http://trustycctv.com/ckfinder/userfiles/files/rubovazefiru.pdfIn PDF document text
    • http://maurovalleferroarchitetto.eu/userfiles/files/30355369466.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/retisuxizavemolixo.pdfIn PDF document text
    • http://theseadiaries.com/ckfinder/userfiles/files/xepivifut.pdfIn PDF document text
    • http://heatexchangersolution.com/upload_fck/file/2021-9-6/20210906190134807874.pdfIn PDF document text
    • http://simoncaulkin.com/images/wemujo.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_off0000c593.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC593 10880 bytes
SHA-256: 9fab0bbcd782dff9433ad910e65f7a886efb417ae8c3fa15ae42e693dd3ebdbd
font_01_sfnt_off0000de8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A1 19656 bytes
SHA-256: 5548702df0b98e2c2665920785429f79044c900d97c9084bb1777c47dfeb868d