Malicious PDF — malware analysis report

Static analysis result for SHA-256 0384f85cccc55713…

MALICIOUS

PDF

73.7 KB Created: 2021-09-16 12:51:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3f928c1b0e1153fb1708fd7ae5bcdb95 SHA-1: 66aa8f48fa7c3a1f31ad306cd8cc33f6bba26dbc SHA-256: 0384f85cccc5571399e80f28952346731212f84e85240f58041a5b7667e3c0db
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are hosted on disposable domains and utilize UTM parameters, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards it being used to redirect users to malicious websites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://pistant.ru/uplcv?utm_term=can+could+must+should+exercises+pdf PDF link annotation
    • https://drivetripper.com/userfiles2020/files/8242031999.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/sabeza.pdfIn PDF document text
    • http://energyexcess.com/userfiles/file/33729225075.pdfIn PDF document text
    • https://ykitraders.com/UserFiles/file/kegekepebirofepiko.pdfIn PDF document text
    • http://socukorglutamatmentesfuszer.hu/ckfinder/userfiles/files/xekiloj.pdfIn PDF document text
    • http://akvatoria.by/UserFiles/files/navunewozabetoxoze.pdfIn PDF document text
    • https://rajatotogroup4.com/contents/files/goxesorewoxasawagadaruza.pdfIn PDF document text
    • http://classicalgardenstatues.com/uplds/file/sitepejinotebiluligotavu.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/28009568380.pdfIn PDF document text
    • https://castilloexterior.org/ckfinder/userfiles/files/xekowojafonulunukor.pdfIn PDF document text
    • https://latgalesamatnieki.lv/files/file/67861945018.pdfIn PDF document text
    • http://denda.co.kr/ckfinder/userfiles/files/519654429.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/nomemisage.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/ludekujifa.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/9vvefvqq31p2i5t8qd3m37r8re/12995274113.pdfIn PDF document text
    • http://camelliafb.com/uploads/files/202109110033508339.pdfIn PDF document text
    • http://agppi99.pretty-match.com/upload/files/rifedi.pdfIn PDF document text
    • http://rcmo.ru/upload/files/jutokoj.pdfIn PDF document text
    • http://cdio.vn/uploads/userfiles/file/gipada.pdfIn PDF document text
    • http://yokohama-model.com/userfiles/files/26179635948.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/b42cd9bac237c609b09eb15de5bcb959/78999592018.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/jokunotilusaxas.pdfIn PDF document text
    • http://sintjorisparochie.nl/userfiles/file/90403715450.pdfIn PDF document text
    • https://webtechnocrats.com/upload/file/lugod.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_off0000bd0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD0F 16264 bytes
SHA-256: 7d818145700d6e0015e60eb647d794b9006c0c2576806f591f8f0809a57ebd72
font_01_sfnt_off0000e71a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE71A 11120 bytes
SHA-256: 6a25c3ddd1e92a05262c89fdd2c7215ae5950102f868b606a543fe1263f4d146
font_02_sfnt_off000100df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1