Malicious PDF — malware analysis report

Static analysis result for SHA-256 a181252a3d69df57…

MALICIOUS

PDF

82.1 KB Created: 2021-09-18 03:13:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: be314f1b0d564d76d2b35f8a44fe53b0 SHA-1: 842a8df1f909f4f10e1b4cc7c12b18d9fd08b8c6 SHA-256: a181252a3d69df5716e40feda3c0fff0f22f72391c3fa5bd8ef068c04e3b6e24
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with a high-confidence heuristic indicating a callback phishing lure. The document body is heavily obfuscated, but the presence of embedded URLs and the heuristic strongly suggest a phishing attempt designed to trick the user into initiating a phone call. No scripts were extracted, limiting the analysis of specific execution chains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 http://back2wood.de/userfiles/file/dogatozonesijinuzunega.pdf In PDF document text
    • https://mavachhaiphong.com/upload/files/37161222806.pdfIn PDF document text
    • http://obrienbuilders.com/userfiles/file/kuwonorezuvaxazuvefurami.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/51725415907.pdfIn PDF document text
    • https://mb-classic-service.de/userfiles/file/novibisopukalojafo.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/ligev.pdfIn PDF document text
    • https://mashtalkandil.com/userfiles/file/lunodetewebinodafalukepi.pdfIn PDF document text
    • http://sushimura1.com/uploads/files/nodikemagudaduzive.pdfIn PDF document text
    • http://centreforeffectivecoaching.com/media/file/52240481075.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/5kidv7lr98oqn6idm0q3g95g3e/gabewok.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/tababoxeliner.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/janamivekopovabixepu.pdfIn PDF document text
    • http://mabo-meccanica.eu/userfiles/files/69247944871.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/31548586426.pdfIn PDF document text
    • http://mh-gartengestaltung.de/userfiles/file/jijumexagete.pdfIn PDF document text
    • http://saraya-shop.ru/upload/files/56668791369.pdfIn PDF document text
    • http://mousike.it/img_ins/files/24927208852.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d56276f44---gonoliv.pdfIn PDF document text
    • https://tybistanbul.org/resimler/files/xijujimuzi.pdfIn PDF document text
    • http://1mosref.ru/ckfinder/userfiles/files/18785898055.pdfIn PDF document text
    • https://alev.az/userfiles/file/72292753931.pdfIn PDF document text
    • http://shanghaicruiseparty.com/uploads/file/20284415387.pdfIn PDF document text
    • http://jpsacademy.com/slbdavbatala/userfiles/file/26094459106.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/dibaxaxetotuvusovowip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=my+talking+tom+mod+apk+2020PDF 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_off0000d5f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F9 10776 bytes
SHA-256: a50ebab101d6b9e0e427be2dc85bf2ecbf3980d74fe9319099cff78cc7fde040
font_01_sfnt_off0000ee85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE85 19644 bytes
SHA-256: 4dea8b051890278daa427158f822afb55d3f0836f1884555d0c4808b0fa350d5
font_02_sfnt_off00012270.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12270 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1