Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5bae90a25e76158…

MALICIOUS

PDF

68.0 KB Created: 2021-09-16 13:50:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 7fb4c47250dbf4ef839ab482093fa836 SHA-1: b87ee26b7db6d174e0c2d999df5de4a8d8362289 SHA-256: c5bae90a25e7615870ecfe0b45c867d8dc2be4e6699547631e3acf9f4b279ffc
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to PDF files on various domains, suggesting a link farm or content distribution network. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple external URIs and the link farm heuristic point towards an attempt to manipulate search engine results or distribute further malicious content, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://le27.fr/docs/file/navijiwi.pdf In PDF document text
    • http://aweibel.com/Photo/file/maxezupuzufizovo.pdfIn PDF document text
    • https://www.potravinyav21.cz/ckfinder/userfiles/files/wofefekim.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/gisawunenuxime.pdfIn PDF document text
    • https://araprinter.com/ckfinder/userfiles/files/fagejirotudid.pdfIn PDF document text
    • https://art-eria.pl/mandarynka/pliki/files/8127451603.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5a097e3cc---febisowozegamunogaz.pdfIn PDF document text
    • http://www.azurwelcomeservices.com/userfiles/file/relejufozoxorijikorip.pdfIn PDF document text
    • http://ksiclubbiz.ksiclub.org/svnprojects/DHD/Source/images/files/25305669595.pdfIn PDF document text
    • https://vitanov.rs/files/6076943071.pdfIn PDF document text
    • http://myphamso1.net/uploads/files/50088513716.pdfIn PDF document text
    • http://geoman.cz/data/file/683219742.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/19146998770.pdfIn PDF document text
    • http://mixline.ru/img/lib/file/bivetofaz.pdfIn PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210912_953C4FF6FA936BE7.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/9ebd2ce8e5e79d8b4b84de545d375203/26244576029.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/29729000112.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/69238210650.pdfIn PDF document text
    • http://vesimport.ru/userfiles/file/zonubusexewukekokona.pdfIn PDF document text
    • http://0851gay.org/userfiles/202109file/2021091605355070554.pdfIn PDF document text
    • http://abwva.com/uploads/files/jinomovubixagaburom.pdfIn PDF document text
    • http://beta-rc.com/upload/files/54809007649.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/96377941145.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=da+tuner+app+free+downloadPDF 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_off0000ad6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD6C 14760 bytes
SHA-256: 1ecc4ae6b44289db48b59d2a635409aab696e83898346a79f06d7944ee579267
font_01_sfnt_off0000d2c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ead9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAD9 10416 bytes
SHA-256: a9b2246e3043422cb651f8374b3a4558e368f462982ea265d60f6c26cb1c3ba9