Malicious PDF — malware analysis report

Static analysis result for SHA-256 81a5b94bbd51b9e3…

MALICIOUS

PDF

68.8 KB Created: 2021-09-16 10:44:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: aaab82fa47d5d494e4eba4eb74d23ed8 SHA-1: 0d2f06fb1525795196619cbf0bde06ee5fdf396a SHA-256: 81a5b94bbd51b9e37bf7c050c944747ed6033ba1792d2f1d2bc6a8c9d4e12dc2
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, and a specific heuristic identified it as a 'link farm on disposable hosting'. This suggests the document's primary purpose is to redirect users to potentially harmful websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://futureinfashion.com/ckfinder/userfiles/files/98258031174.pdf In PDF document text
    • https://villadelauca.com/userfiles/file/76044081308.pdfIn PDF document text
    • http://gmtshipping.com/attachment/file/zafip.pdfIn PDF document text
    • https://verandapattaya.com/userfiles/files/21785407431.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/5854355392.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/5224247526.pdfIn PDF document text
    • http://metamorfoza-krosno.pl/userfiles/file/35174517294.pdfIn PDF document text
    • https://instalacje-elektryczne.net/ckfinder/userfiles/files/texapazuperorenevufuju.pdfIn PDF document text
    • https://moderator.lt/components/com_mijoshop/opencart/image/data/files/jojatasibum.pdfIn PDF document text
    • http://spakimthi.com/upload/files/96325390292.pdfIn PDF document text
    • http://bekkercoon.ru/ckfinder/userfiles/files/jinijapofa.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210903233301.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/xojiwukej.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/wadarebumikopagukog.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/pilatiduxez.pdfIn PDF document text
    • http://foreverymuslim.net/home1/forevev3/public_html/foreverymuslim/upload/file/punuguxavutisor.pdfIn PDF document text
    • http://1carl.com/userfiles/file/63791412948.pdfIn PDF document text
    • http://icsbc.ru/fuploader/file/59401847410.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/narinikax.pdfIn PDF document text
    • https://www.displaysdirectaustralia.com.au/application/third_party/ckfinder/userfiles/files/zabamiriforubafudoz.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/jedepowodijivow.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/20639326719.pdfIn PDF document text
    • https://md-bud.pl/szklo/photos/file/8308621269.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/8v7522omiu5peb3t9o4o84papk/44257940561.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=vpn+free+internet+hackPDF 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_off0000b0b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8CA 15116 bytes
SHA-256: c1e544ebc4c3e9cd42374d3d252f52e7ed8b6b71ae97142de6fd5670774f08d8
font_02_sfnt_off0000eed5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED5 10304 bytes
SHA-256: 06dc5db6aa67798937989150c64b2e6e631b3b9262190249e17df057be4115e5