Malicious PDF — malware analysis report

Static analysis result for SHA-256 f684a1a061feb877…

MALICIOUS

PDF

70.5 KB Created: 2021-09-14 10:23:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 270ebedae9776323d17420bd86cdc87e SHA-1: 99cd58f231f93b0e66c6fe90c132899b881c2c55 SHA-256: f684a1a061feb87700e404c09abdbbd6287145eed962de7074d01c865f5f8c86
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various PDF files hosted on different domains, indicating a link farm or distribution network. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is not a legitimate document but rather a tool for SEO manipulation or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://kolbiko.com/images/uploads/file/ronodizomewuware.pdf In PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210908030345.pdfIn PDF document text
    • http://bestbuyfromindia.com/userfiles/file/16011366357.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/xiweveduwevawitopeva.pdfIn PDF document text
    • http://hainescentreasia.com/images/file/limirometugodawuv.pdfIn PDF document text
    • http://voszveszprem.hu/_user/file/12782067886.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/52872977737.pdfIn PDF document text
    • http://ganteltechnology.com/system/userfiles/file/bixupatimufawolatemem.pdfIn PDF document text
    • https://triptoboloyfoundation.org/editorsfiles/files/ralomemusexojobikezopiv.pdfIn PDF document text
    • https://shriayurvednagpur.org/public/ckfinder/userfiles/files/gelekobekipupazurazaz.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/xawepivujani.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/6e396ec55818c899b28a17561379df0e/25871175071.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/tomapozezemalipewaze.pdfIn PDF document text
    • http://josepholszowka.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9521380960.pdfIn PDF document text
    • https://capital-publishing.com/ckfinder/userfiles/files/83212711143.pdfIn PDF document text
    • http://agriturismocorteerbatici.it/userfiles/files/86949966769.pdfIn PDF document text
    • https://ciela13.leaddeehub.com/userfiles/files/nafivepurigotabiburizo.pdfIn PDF document text
    • https://laps.pl/userfiles/file/73545114664.pdfIn PDF document text
    • http://bakineshr.az/ckfinder/userfiles/files/59647045744.pdfIn PDF document text
    • http://kovofilm.cz/userfiles/file/53835858865.pdfIn PDF document text
    • http://rc-modeller.se/images/file///ravepevutobaduw.pdfIn PDF document text
    • http://sitarofindiamd.com/userfiles/file/xoxosamot.pdfIn PDF document text
    • http://surveycook.com/upload/tmp/202109/file/diwusozejupo.pdfIn PDF document text
    • http://gpsputhuppally.com/userfiles/file/nopavuvivopolivibubixi.pdfIn PDF document text
    • http://www.tamtrebinhminh.com/public/files/vujidobalazulisesewosag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=insta+big+profile+photo+apkPDF 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_off0000b688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB688 14924 bytes
SHA-256: c60984329ba2329da6e8ded02337fbd997ef9a92b080dc9c76e14c7854cd1005
font_01_sfnt_off0000db66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB66 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f37d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF37D 10820 bytes
SHA-256: c31470aaa73673f75f0a0945eae350ddb44bde9ecfb8e4253b4fb1c78d376135