Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc6afa98d80e24b6…

MALICIOUS

PDF

80.5 KB Created: 2021-09-18 15:58:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b3d032dea7e7cbcae6e60c3be9cf630e SHA-1: b9c4808e1ad90e4e451a5f6dea48d9bcbbcdfbb6 SHA-256: fc6afa98d80e24b6f30ee4a555c28d3f16f4ea2ee237e5c2868eedcc0d78380f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous external URLs were extracted, suggesting the PDF acts as a lure to redirect users to potentially harmful websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating a pattern of using disposable hosting for link farms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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.
  • 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://krisoc.ru/uplcv?utm_term=truecaller+red+call+symbol PDF link annotation
    • http://motolargo.pl/userfiles/file/72941904620.pdfIn PDF document text
    • http://www.saaegfpolis.org.br/ckfinder/userfiles/files/vakemevezozogev.pdfIn PDF document text
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/13996363615.pdfIn PDF document text
    • http://german-ex.com/images/blog/file/fugigekolutoxejejoso.pdfIn PDF document text
    • https://llibreriaha.com/img/events/file/kuxuzipiri.pdfIn PDF document text
    • https://www.pactforfamilies.org/ckfinder/userfiles/files/lidevefukamu.pdfIn PDF document text
    • http://niszczeniewaw.pl/userfiles/file/7263569704.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/11716421966.pdfIn PDF document text
    • https://styliststudios.com/imagesTE/file/terexinejuwanusa.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145cf4c346a9---2284336101.pdfIn PDF document text
    • http://villacappuccina.com/userfiles/files/xikijagudareramebekize.pdfIn PDF document text
    • http://hrzservices.com/uploadfiles/file/voxarowipudalaruxi.pdfIn PDF document text
    • https://nangluongvada.com/uploads/files/zuwidazura.pdfIn PDF document text
    • http://kingbikeonline.com/images/upload/File/zedazazuwomemorus.pdfIn PDF document text
    • http://gordostcrista.ru/userfiles/file/tawawemexiberubomezozus.pdfIn PDF document text
    • https://evpersoneli.net/ev-personeli/file/76395458197.pdfIn PDF document text
    • https://gentrilieu.vn/userfiles/file/55484875761.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/36956893961.pdfIn PDF document text
    • http://gerd-pollak.de/userfiles/file/kuzefufadizivilejijet.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/75174449787.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/sajevivijonorivoke.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/5009997509.pdfIn PDF document text
    • http://koryosushi.com/uploads/files/ropux.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_off0000d693.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD693 17884 bytes
SHA-256: 0e18ead4b6fab3ce6e41219f8d919f6eb0c1099c4570cb55fff65c98bec69c88
font_01_sfnt_off0001043e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1043E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C55 10552 bytes
SHA-256: 3d49844ae00325df0aa16b15195b875e0c55ed1e1742f8d2553ef960272ac219