Malicious PDF — malware analysis report

Static analysis result for SHA-256 b461c35a826144c8…

MALICIOUS

PDF

81.1 KB Created: 2021-09-21 22:31:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4627f183e5b3cb5a3a2801c27e756d27 SHA-1: e47504be6f2416c235ecb289811e38abb9c29245 SHA-256: b461c35a826144c8372bfaadbd4bb9fe335361ef4401c7eb6982f3babe554e85
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external URIs and is structured as a link farm on disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of embedded URLs and the overall structure point towards a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://chcial.ru/uplcv?utm_term=android+11+update+list+redmi PDF link annotation
    • http://moskvaznaet.ru/upload/files/68426604895.pdfIn PDF document text
    • http://familiegravesen.dk/userfiles/file/24984703677.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161408e05e6083---komuzojozesetigopap.pdfIn PDF document text
    • https://ambalatender.com/upload/files/tigejuzojebilog.pdfIn PDF document text
    • http://fecirturizm.com/resimler/files/nezusule.pdfIn PDF document text
    • http://amicissiapiemonteisa.it/userfiles/files/ruzunuwelopu.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/7123483258.pdfIn PDF document text
    • https://airxps.com/userfiles/files/xativafolepojagabipusoref.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/mobabisifodet.pdfIn PDF document text
    • http://cbafjvn.com/uploads/userfiles/file/xazomutinafosuferexub.pdfIn PDF document text
    • http://nature-revive.org/files/file/94790258898.pdfIn PDF document text
    • https://drproperty.in/userfiles/file/24206353065.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/161401d505eff6---26732783060.pdfIn PDF document text
    • https://www.corpeverest.com/ckfinder/userfiles/files/bipebajutevamizezo.pdfIn PDF document text
    • http://afslab.asia/upload/files/delam.pdfIn PDF document text
    • http://sm.ac.th/ckfinder/userfiles/files/mebamexowosufotemonikid.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/5778915385.pdfIn PDF document text
    • https://heritran.vn/uploads/news_file/wukavud.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/928149192.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/pilolalosurelatidogabelef.pdfIn PDF document text
    • http://pes.edu.mn/ckfinder/userfiles/files/jumiguworeliluboki.pdfIn PDF document text
    • https://penzehir.com/dorceiys/ckfinder/userfiles/files/8710667341.pdfIn PDF document text
    • http://phuongdonggolf.vn/app/webroot/uploads/files/jowonabagadazujeruv.pdfIn PDF document text
    • https://nhaccugiare24h.com/uploads/userfiles/file/91933304571.pdfIn PDF document text
    • https://z87992961.com/upload/files/20210909105922.pdfIn PDF document text
    • https://congnghieptauthuyvietnam.vn/upload/files/meduloritunemunabobusu.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_off0000d7d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEF 10684 bytes
SHA-256: b5ec9bf79f11ad08f31c0387596cd21388cc44df30e39a67f40b5748cda3b641
font_02_sfnt_off00010874.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10874 17916 bytes
SHA-256: 111cd60265ad08acb7c3fa9ffece8a1d71a93f63b32ca78e15101c7055d09a24