Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4f2c1a88e47aaca…

MALICIOUS

PDF

97.3 KB Created: 2021-09-01 10:36:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 16d0ef3708859b1f6d66990e7a50aad8 SHA-1: c4509ffab8ec465913d43c7caed81899f3399d88 SHA-256: d4f2c1a88e47aaca7e879eec74c3b57259d97bf19ba19d55a93c47a857610065
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis confirm the malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607426e660fe5---47113106431.pdf In PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/d1kg6ec0mkua985t04d3smr3ae/61932246849.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cded2c8afa6---nivujokutuw.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16073a36a7a007---mumelovibatepebukevuxi.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///63140309910.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/n1qinqnqe9tmbcg3ll2b202svh/kavumoxexiwoneriwujed.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/doluxaruxujuwapag.pdfIn PDF document text
    • http://feuerwehr-mittenwalde.de/mediathek/files/84031036301.pdfIn PDF document text
    • https://mmeasar.com/mmeasarfiles/file/63634493620.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/dufutegukizinilozifa.pdfIn PDF document text
    • http://modero.vn/upload/files/78974374721.pdfIn PDF document text
    • https://hoalavender.net/upload/files/57534636371.pdfIn PDF document text
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/21066675297.pdfIn PDF document text
    • http://geredekombiservisi.com/userfiles/file/gexalanonizumilateza.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/f3c20323764f03ee44696f71ca218861/504713689.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/48423922399.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160855e68dd287---57892240505.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/zukorolo.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a96900b0c1---73006004285.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=sixth+schedule+of+sales+tax+act+1990PDF 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_off00011710.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11710 10988 bytes
SHA-256: c0b60961197f4d58624489c774e136e6eca11b9f7ac7d35df405d09acd45022d
font_01_sfnt_off000130c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130C2 17784 bytes
SHA-256: 51fb6101ac771e1f73406318fa0c362b734807bc1f0697f9630ee9b2b3e1dd95
font_02_sfnt_off00015ed8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15ED8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1