Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8fb4fba1c6f5974…

MALICIOUS

PDF

84.9 KB Created: 2021-07-02 20:30:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 6c4ff7866f2e7fcde53c8af4744cf0ef SHA-1: 1c21ad663b9ed243d6419677cc4fad7c9c1a1eaa SHA-256: a8fb4fba1c6f59748b5a4919a89308468db6188510433368e73219f73ae800f6
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress sites and other disposable hosting. These links likely lead to phishing pages or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://catamma.ru/uplcv?utm_term=php+parse+file PDF link annotation
    • http://ildongwire.com/userfiles/file/jusijinukupuv.pdfIn PDF document text
    • http://nitexprofi.cz/userfiles/file/31591730605.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/4fa10d2977d73d5967a06c20069ec94d/xagab.pdfIn PDF document text
    • http://phannhan.vn/files/usersfiles/files/42846761539.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc625a9b67b---ridujav.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160706b32292f6---gibedelisedetilomofaba.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef59d30b13---65327487964.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/7a6797e72899053882e24a8d0e8de38b/wokafujaxadajadaw.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1606c99f4876b3---fubita.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16071e8f64a2e9---45646521641.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc5fda39a6---kurileme.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/94b4fb896a4a4e18fe058729f1df5e8f/95468871852.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cffdb1d1b1d---zisixumebekazagisonixixon.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/9a3p0qkf8mna8co75eofsle0dg/66134989683.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/lasidasusikes.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160c9750bce749---lasobetupimitejefizin.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/1d06a53132bc699704ecda1f27167433/81130981041.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/5a9d822d4d03c934e00f08d106c5cb40/wesanepugi.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/20957e34a68ba495be99c7a3df1839d8/61348086818.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/duvox.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160770fb76b13c---99066233378.pdfIn PDF document text
    • https://coluer.ir/documents/file/30244274647.pdfIn PDF document text
    • http://cs-web-design.de/ablage/userfiles/files/16686402067.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/39831101002.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/24187368873.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/402fbb7bd6201cf5fded90e4b316784a/51447890480.pdfIn PDF document text
    • https://www.ndgai.com/wp-content/plugins/super-forms/uploads/php/files/h210rr9pa83mk1l9ol13v7rge5/93866888464.pdfIn PDF document text
    • 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_off0000e9b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B7 17580 bytes
SHA-256: fc236f4b21b688c3b18cc5671a947dd6248ef8ffc1f87ae9f494d9bba0a7d3c7
font_01_sfnt_off0001179a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1179A 10136 bytes
SHA-256: e942a37e249c5e5eacf10046368d6743fbd34ff686cf273ac3018efdac23a9a8
font_02_sfnt_off00012e4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E4F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1