Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ded5160d8ef306f…

MALICIOUS

PDF

96.7 KB Created: 2021-08-07 05:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 30a35146d629db412f5ce3338140e090 SHA-1: 7f7214bb584b9ffa3ced1e58d9f8110ddf7e3304 SHA-256: 8ded5160d8ef306f13fba87a554b2b8cd56dba6c5ada38dda0e96407b959db34
164 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to potentially compromised WordPress upload storage. The embedded JavaScript likely serves to execute malicious code or redirect the user, while the link farm attempts to obscure the final destination, which is likely a phishing or malware distribution site. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM suggests a tactic to leverage disposable or compromised hosting for distributing malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nestuby.com/userfiles/file/22645442082.pdf In PDF document text
    • https://svetplus.com/userfiles/files/91092162881.pdfIn PDF document text
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/nurad.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/0b323bjqpughcaa2cb545vhude/jegefikagejuba.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16074a415076e2---35967071445.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/44b36a69dcd3d8bea8d4b8b2c6ba53d3/mewesilidatanidiwurosugo.pdfIn PDF document text
    • https://proia.bg/userfiles/file/99204959929.pdfIn PDF document text
    • https://cristalensi.com/public/File/60780629828.pdfIn PDF document text
    • http://ricarda-allegra.de/userfiles/file/xudiwezenafoxedus.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/46287595503.pdfIn PDF document text
    • http://sumtinathholidays.com/admin/uploadfiles/file/11511092800.pdfIn PDF document text
    • http://langmypham.com/luutru/files/rivuxinu.pdfIn PDF document text
    • http://zerosquareonline.com/file/36752025763.pdfIn PDF document text
    • http://sysquare.com/UserFiles/files/23585324538.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16085980d451c8---zeleb.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/61926222254.pdfIn PDF document text
    • http://styropapex.pl/userfiles/file/folebumenoku.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/vugonudip.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/e60883a602313c4b1e977f27c8912d5f/velevewazibodavoj.pdfIn PDF document text
    • http://inistor.com/ufiles/files/gawazilolojojika.pdfIn PDF document text
    • https://burgaseguros.com/userfiles/file/kiloxum.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=novation+impulse+49+sizePDF 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_off000114ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114BA 10764 bytes
SHA-256: e5c3ac668203c4603861c386ac78fb71dbfe5f52e33fa6d3b58ea02b63521684
font_01_sfnt_off00012d97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D97 18068 bytes
SHA-256: 5c60eac1cfdf674575fb8d6569d62d71d5eabe7120dbcd104f6ccab2f4c26dc0
font_02_sfnt_off00015d00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.