Malicious PDF — malware analysis report

Static analysis result for SHA-256 28d23b732ba8ef60…

MALICIOUS

PDF

79.7 KB Created: 2021-09-13 07:11:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d047e4306339d0f91bd7291cec13f911 SHA-1: 899846c48885ac582a4973f43778612b4a954459 SHA-256: 28d23b732ba8ef600e97a754d318468f21c5768f0e84fecb457699b4a8b4b759
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics confirms the link farm nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crysiq.ru/uplcv?utm_term=tiny+flashlight+app PDF link annotation
    • http://netinflux.net/userfiles/file/34623109513.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613661ea8f3a1---jivogubimujopo.pdfIn PDF document text
    • http://coral-travel66.ru/admin/ckfinder/userfiles/files/pasakoraboxizagenefonip.pdfIn PDF document text
    • http://lawyersmarketingusa.com/user_upload_image/file/In PDF document text
    • http://timnhanhonline.com/upload/files/85789211127.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9a0569451---lefot.pdfIn PDF document text
    • http://ltptech.vn/uploads/userfiles/file/32836711932.pdfIn PDF document text
    • https://machnik.net/ckfinder/userfiles/files/26567418165.pdfIn PDF document text
    • http://inhome360.ru/admin/ckfinder/userfiles/files/17721064194.pdfIn PDF document text
    • http://ivelinabozilova.com/userfiles/file/wuwuzuwiv.pdfIn PDF document text
    • https://glaze-metalart.com/upload/files/rasujanulemurolusopukov.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/44448509571.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/lavotaxopoxexodolugo.pdfIn PDF document text
    • http://namjapizza.com/app/webroot/files/ludilu.pdfIn PDF document text
    • https://bdprescription.com/ci/userfiles/files/22859067320.pdfIn PDF document text
    • http://warmistore.com/userfiles/file/59813274672.pdfIn PDF document text
    • http://bienbao.net/uploads/files/32627375321.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/84721310896.pdfIn PDF document text
    • http://abc-tel.ru/data/File/41853521314.pdfIn PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/pigosuzofawogunedo.pdfIn PDF document text
    • http://bratislava.topenglish.sk/app/webroot/gallery/files/furete.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/79055980863.pdfIn PDF document text
    • https://szallas-karpatalja.hu/upload/detozi.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/0b52af052d1d84f17e2a659e4b0336fe/wafosiwoxoxetatofo.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_off0000ccbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e4d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D1 20436 bytes
SHA-256: 896b95fae0a7d8acdae7cc8a87c0e68a88604ac1cdfeece9691ccc94e3509c8b
font_02_sfnt_off000119a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119A1 10364 bytes
SHA-256: 2b2105ef575715c7a7bb9828bf66cd926aa641f7d8d5d404f064988d844f92fd