Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb4b99326a8b9999…

MALICIOUS

PDF

76.5 KB Created: 2021-09-17 10:35:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6dd610d7879d545e28d38c39eb0e6013 SHA-1: 69f1b8bafbc4941c8416873910cf6cb318769c50 SHA-256: fb4b99326a8b999991c31af979e445c277d392317fc28a377cc10d24aa53bcc4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Numerous external PDF URLs are embedded, suggesting a phishing or malware distribution scheme. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of malicious intent, likely related to spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 https://unitytradecapital.com/ckfinder/userfiles/files/19287933870.pdf In PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/49567229938.pdfIn PDF document text
    • http://innospectrum.eu/hirlevel/file/81560655927.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/diburoxozisegubori.pdfIn PDF document text
    • http://fpole.ru/sadm_files/6239429046.pdfIn PDF document text
    • http://area100impianti.it/userfiles/files/dijabiwanowiw.pdfIn PDF document text
    • https://medarbindia.org/ckfinder/userfiles/files/43314701377.pdfIn PDF document text
    • https://techlan.pl/files/file/jemuv.pdfIn PDF document text
    • http://skisun.it/userfiles/files/vepipekenisik.pdfIn PDF document text
    • http://vnndt.com/Images_upload/files/48098129566.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/xekenekis.pdfIn PDF document text
    • http://fohow77.ru/upload/file/tijodiverabowag.pdfIn PDF document text
    • https://ever.dacola.com/upload/files/lidogegirezaluguxipi.pdfIn PDF document text
    • http://hortherbpublisher.com/files/upfiles/file/duposorumew.pdfIn PDF document text
    • https://kingbakerypans.com/userfiles/file/vumoniluwawedetabaxonawen.pdfIn PDF document text
    • http://carrozzeriardue.it/userfiles/files/10277209420.pdfIn PDF document text
    • http://studiogalata.it/userfiles/files/jabusizamepajipugi.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1631439918.pdfIn PDF document text
    • https://tyko.pl/userfiles/file/vimomebotogiwisanebulopo.pdfIn PDF document text
    • https://comillaspostgrado.es/userfiles/file/79897125613.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/410a27cc0a59034c7dc1ddfc31936014/zijeroposobalerubanuw.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/4081ed9e0df74d3c8092b5dc9c851275/sedidulowedibuzuwex.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/wizoxipazeg.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/mudikemowawibe.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/webadivararas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=analysis+bet+hacked+apkPDF link annotation
    • 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_off0000ce1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE1B 10716 bytes
SHA-256: a2f048334af8526e0fb68293a37d0d202455afc28fac3ad5f8d57c56892e316e
font_01_sfnt_off0000e684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE684 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE96 17380 bytes
SHA-256: 1a32324c47223853ec5613612d089f72175eb69cd36fc009059a924d51bd3a75