Malicious PDF — malware analysis report

Static analysis result for SHA-256 d43f1d4cdeba0e06…

MALICIOUS

PDF

85.8 KB Created: 2021-07-16 07:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 400dd1bcabefda2c5a373533a86fca53 SHA-1: c5ae5e732b9f0f630f6c9b83449916929d970fa2 SHA-256: d43f1d4cdeba0e063f8f035c66c10d2d8440eed7d1be991523ecad0d10f60ff6
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to compromised WordPress sites, suggesting it's designed to lead users to malicious content. The document body is heavily obfuscated and unreadable, but the heuristics indicate a link farm structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://pistant.ru/uplcv?utm_term=stereograms+with+answers
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd2438b81c---57610744624.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16086c7e5ccd58---57857145204.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/381456724dc8a18b4cd43fa21a1588c8/purulowawamoxugodin.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085e9b913f2e---99448493012.pdf
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/77facf137470607b5c165e486f03e74c/99851140889.pdf
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/7a52df913703b65515a5495dd67ab957/babasaros.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bb10e98f59e---bupilorowezeb.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609884383d508---lijozesipanupujotur.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/e79625a8c556e2545b78340707a460df/57038604537.pdf
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c0a92208425---55087998567.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609d1a425614d---xumadedupugufogi.pdf
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdafc1cf86b---roxezomanejovujavitokures.pdf
    • http://urbancollab.com/userfiles/Proj_Name//files/84803284786.pdf
    • http://sbox-technology.com/upload/datoteke/kewisumuwisus.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f6d225537b---67235711963.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070144c690e8---fugomeluwopigawala.pdf
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/17337143304.pdf
    • http://prabashproperties.com/ckfinder/userfiles/files/41576536095.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/075992f610f94cf46f873cb0bd2d1917/71922457367.pdf
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/v4jc0o67he8rv24h0bt9q0qnev/kedajafixoxarujazavekub.pdf
    • http://s8radziejowice-paszkow.pl/userfiles/file/15281220544.pdf
    • https://total-sport.pl/img/upload/files/21204998662.pdf
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/61961658781.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eea8.bin
89fcb0e3b1060a201ed355f7e44f174f03ee1b1bf30cc75f155f72c0d8b41ea6
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA8 10668 bytes
font_01_sfnt_off00010700.bin
658ae96d1ddb98d5a78bfaff27f79b9540b2b386e1177649aedc60f357facec2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10700 16892 bytes
font_02_sfnt_off0001332e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1332E 16792 bytes