Malicious PDF — malware analysis report

Static analysis result for SHA-256 da3b088d44cd86c5…

MALICIOUS

PDF

73.5 KB Created: 2021-09-19 12:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a02bcb1d645b59e5d086a882a52f4174 SHA-1: 8effc084397d12b40ff774899a7731a6313886cb SHA-256: da3b088d44cd86c564caf6f9fac194baffa2c43365f940912d959cc93e6e54b3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm with numerous links to disposable hosting, suggesting an attempt to redirect users to malicious sites. The embedded URLs, such as http://erpsamik.com/ckfinder/userfiles/files/42982079436.pdf, are likely part of this redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://erpsamik.com/ckfinder/userfiles/files/42982079436.pdf In PDF document text
    • https://eetravel.net/file/sowezuxikewuludopekuwud.pdfIn PDF document text
    • http://urduhadith.org/survey/userfiles/files/28816803123.pdfIn PDF document text
    • http://galeriejacqueselbaz.com/userfiles/file/febenokizapexogevigejudi.pdfIn PDF document text
    • http://ccspatti.org/userfiles/file/44404631576.pdfIn PDF document text
    • http://ominocoibaffi.it/userfiles/files/femovevomovofufuzezoto.pdfIn PDF document text
    • https://kocarbon.vn/luutru/files/japeveravugipologabi.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/c9878a3d9666154ef6289ad692830d18/47430340727.pdfIn PDF document text
    • https://flour.co.uk/ckfinder/userfiles/files/rutudatukupagesun.pdfIn PDF document text
    • http://viorina-deko.com/images/file/81754813507.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/wolominuvis.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/17866614555.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/99200788877.pdfIn PDF document text
    • http://solar-makernavi.com/ckfinder/userfiles/files/49483336314.pdfIn PDF document text
    • http://ageddfjtj.pretty-match.com/upload/files/xedikofilen.pdfIn PDF document text
    • http://budaors.varosom.hu/userfiles/files/928699632.pdfIn PDF document text
    • http://amicissiapiemonteisa.it/userfiles/files/10321848111.pdfIn PDF document text
    • http://xn--eyt274i.com/upload/files/23993308000.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/bc0d5232baaec2aedb539931907e1e9c/54362043068.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16136cf246d52c---vebebud.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109140630359157.pdfIn PDF document text
    • https://cuichi177.com/uploads/files/202109032053286382.pdfIn PDF document text
    • http://canadianrockies.info/files/file/47415754226.pdfIn PDF document text
    • http://elektron.be/public/userimgs/files/75888551098.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=minecraft+cat+house+designsPDF 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_off0000baeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAEB 17724 bytes
SHA-256: a62fa2a32a354130ae4931fdb1c5b72e3695e7c8e5f65edf7895c612b70f673a
font_01_sfnt_off0000e803.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE803 10800 bytes
SHA-256: 69a51f34276cce1b6c0bccce81f90b72722d9012664e7cd89379f13a6de15d68
font_02_sfnt_off000100a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1