Malicious PDF — malware analysis report

Static analysis result for SHA-256 160c22dff68dff40…

MALICIOUS

PDF

71.0 KB Created: 2021-09-27 01:53:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 814809153b42ecf43ba53c102367390f SHA-1: 73d30bd289980501b0c8e79ce991b995341cdca7 SHA-256: 160c22dff68dff400e3b872aafe47b051cf050c8fd432f7321cf30d33431f315
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ML classifiers and ClamAV, specifically flagged as Pdf.Phishing.Trojan. It contains embedded JavaScript and a large number of external URIs, many of which are on disposable or link-farm hosting. The embedded JavaScript likely facilitates the redirection to these external links, which are presented as download opportunities, a common phishing tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://queure.ru/uplcv?utm_term=download+minecraft+for+free+on+tablet PDF link annotation
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139f6ac5524b---18141464277.pdfIn PDF document text
    • http://freeorden.com/media/file/ribalu.pdfIn PDF document text
    • https://preciseenergygroup.com/media/22114735094.pdfIn PDF document text
    • https://cissud.it/uploads/ck_editor/files/44214701972.pdfIn PDF document text
    • http://directartdeal.com/uploaded_files/userfiles/files/tezixal.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/xukufijuniwalejibekit.pdfIn PDF document text
    • http://edeins.com/userfiles/file/38770058205.pdfIn PDF document text
    • https://democv.associasuite.com/imagenes/contenidos/files/26256308480.pdfIn PDF document text
    • http://wolfpackbasketballacademy.com/content_docs/24879009130.pdfIn PDF document text
    • http://svsteinfurth.de/radsportfiles/file/42017121977.pdfIn PDF document text
    • https://corianderedmonton.com/ckfinder/userfiles/files/55349474051.pdfIn PDF document text
    • http://sourceandsecure.com/uploads/userfiles/file/memuvivi.pdfIn PDF document text
    • http://karaokejdi.com/ckfinder/core/connector/php/upload/files/lumurenib.pdfIn PDF document text
    • http://shrlie.com/upload_fck/file/2021-9-6/20210906185310766764.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210909193853.pdfIn PDF document text
    • http://rockhouseschool.com/rockhouse/uploads/files/sipeseta.pdfIn PDF document text
    • http://plovdivweek.com/app/templates/js/ckfinder/userfiles/files/77559460039.pdfIn PDF document text
    • http://xn--3bsx3iw22bmot.com/filespath/files/20210910233554.pdfIn PDF document text
    • https://matricula.arendic.cl/files/69174476651.pdfIn PDF document text
    • http://etasystem.net/userfiles/files/putoxixeb.pdfIn PDF document text
    • http://mstreatmentadvances.com/userfiles/files/15496693879.pdfIn PDF document text
    • https://ijacr.net/assets_admin/ckfinder/core/connector/php/uploads/files/5825173228.pdfIn PDF document text
    • http://landonintergroup.com/ckfinder/userfiles/files/13953048392.pdfIn PDF document text
    • https://apexsafetyproducts.com/ckfinder/userfiles/files/pexifosokofexoligad.pdfIn PDF document text
    • https://jamisonfurnace.ca/userfiles/files/62881124711.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/xefidovugivuliriduzan.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_off0000b536.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB536 15688 bytes
SHA-256: 92cc4759e07bbddead91642d797e8b8c37d4220ab1bec9b1da9ac73359502222
font_01_sfnt_off0000dd51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD51 10696 bytes
SHA-256: acb228e53a2362e453bcdbcede8011bbc4d906d4fb4637859314464939514284
font_02_sfnt_off0000f5d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1