Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3dcc7066e56752b…

MALICIOUS

PDF

84.5 KB Created: 2021-09-16 09:37:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2ceb4603ca548bd314bc97132b571052 SHA-1: a168064dec020ee18ab4511fd6b8fc45d8dc3fbe SHA-256: a3dcc7066e56752b245cf18004add15fd8ca478f89f5137aa9945ae8649fea2e
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as a malicious PDF by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting and appear to be part of a link farm. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a high likelihood of this document being used to redirect users to malicious sites, potentially for phishing or further malware delivery. The presence of embedded JavaScript suggests an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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://philabc.ru/uplcv?utm_term=gazi+tv+online PDF link annotation
    • http://thecountryclub32055.com/userimages/mugewetudegisusatukexe.pdfIn PDF document text
    • http://netichikawaya.com/userfiles/file/81123113394.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/90078112213.pdfIn PDF document text
    • https://mklaassen.nl/images/file/11262463867.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/12054619794.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/84229173399.pdfIn PDF document text
    • http://marasintl.com/public/ckfinderuploads/files/69576049983.pdfIn PDF document text
    • http://betonkeritesek.eu/Content/files/82492468577.pdfIn PDF document text
    • http://xn--80aagkbrca3apkgkee0a1bi.xn--p1ai/ckfinder/userfiles/files/rulonupizonuxi.pdfIn PDF document text
    • http://larben.cz/media/images/upload/file/355422309.pdfIn PDF document text
    • http://espressobuilders.com/app/webroot/files/userfiles/files/97597036218.pdfIn PDF document text
    • https://traffictkt.com/viking1/uploads/files/86661013419.pdfIn PDF document text
    • https://dukupahit.com/contents/files/48467788440.pdfIn PDF document text
    • http://www.oomewatersport.nl/upload/files/84403166557.pdfIn PDF document text
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/62478581275.pdfIn PDF document text
    • https://dazhonghua1688.com/ckfinder/userfiles/files/kebonozejaguvanuro.pdfIn PDF document text
    • http://kurumakaitori-one.com/js/upload/files/xigakawidof.pdfIn PDF document text
    • http://stjconsulting.it/userfiles/files/17292768730.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613648041cfd2---35664070369.pdfIn PDF document text
    • http://auto-rad.pl/userfiles/file/godekiminetilonaxixanox.pdfIn PDF document text
    • http://naturenhuman.com/app/webroot/userfiles/file/xapifojitotiviwazulanedo.pdfIn PDF document text
    • http://unibeauty.com.br/ckfinder/userfiles/files/57497935140.pdfIn PDF document text
    • http://tpdw.pl/userfiles/file/25466974111.pdfIn PDF document text
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/45414748595.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_off0000e713.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE713 18340 bytes
SHA-256: 3a694b12b9ea5e106735a21b33649898e27639801610ac88d9f4bc29ee842894
font_01_sfnt_off00011646.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11646 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E5D 10000 bytes
SHA-256: ea4b83aaa501f4cd4a45347a4d8b6bea27bdd47b29d18158ca20a059bf984124