Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5b21f0a1e197a3f…

MALICIOUS

PDF

91.3 KB Created: 2021-06-27 01:43:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b182931374325f3167536638655f48a6 SHA-1: 10fdc3433290285c71398bafe536b5da1740264f SHA-256: f5b21f0a1e197a3fbfc832ca94e289ccfedd563aad06bc34e211f64f2e8aac21
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and disposable domains, likely intended to redirect users to malicious content or phishing pages. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, noting the use of disposable hosting and UTM parameters for tracking redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://crewmak.ru/uplcv?utm_term=bash+out+meaning
    • https://aonetreks.com/uploads/file/5198234376.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/59a9888c45635fe8c4ffc152bd168936/zobej.pdf
    • http://kuehllawpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/15161544561.pdf
    • http://com123.vn/uploads/file/71298021943.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c4122bd80---50161380319.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/8vjue14f2q5cqfq65t3leees6n/gofowuvomima.pdf
    • http://gorisum.net/fckeditor/upload_file/file/gexivosigitapum.pdf
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab7671afe85---24031977662.pdf
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/541a2a63a1fe96bc2c9d8ab50addd1b0/nagudewop.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071991adbefd---pixagepifi.pdf
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/fb653a959f2148fb558411e9504e11a1/21580202782.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1276e88cad---zujonofodufowetilap.pdf
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/dfef57fd2132f55b630c7d27bf599e63/10706555952.pdf
    • http://goref.ru/files/file/1559611124.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608793b32c198---30997903247.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607838069ab03---xexekomit.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16078d8cc5d5ad---56621986624.pdf
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607243465e06d---57051515640.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/snf5f0sun24est0298vsigkii1/7894430549.pdf
    • http://webcertain.net/contentupload/fckeditorUploads/organization_/file/35545527843.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084af6476e78---vosinikemobijewi.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087218d8e9c4---kiwuxawivawededizumusam.pdf
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021061405544780554.pdf
    • http://cs-web-design.de/ablage/userfiles/files/nelalubanegijiruge.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160772bb1e4448---pufapu.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_off0000ffc6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFC6 16792 bytes
font_01_sfnt_off000117d8.bin
d95c43752c92d4416ed327408c966f2652fc7143587ebcad370039f356ac8ec8
pdf-font-stream PDF embedded font (sfnt) at offset 0x117D8 18532 bytes
font_02_sfnt_off00014832.bin
7ffadb586814834c145bf24782afb33bac8d4d1320aca9d91dec9a70e899ad56
pdf-font-stream PDF embedded font (sfnt) at offset 0x14832 10564 bytes