Malicious PDF — malware analysis report

Static analysis result for SHA-256 19457ca8db429b77…

MALICIOUS

PDF

89.1 KB Created: 2021-08-04 18:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: a288415e962455da51d0de41d6a27bc5 SHA-1: 4ddc07130cc0943f0c255d07a2f9e7d4f65663ef SHA-256: 19457ca8db429b7764a95849251e419024d959d803a8b4743aa251e1e01604ec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://queure.ru/uplcv?utm_term=lcd+led+tv+repair+manual PDF link annotation
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16100261a3d050---nevakutupijudax.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/31b5f0b01ffd4ff9770e742a2172bbb4/zamibejiru.pdfIn PDF document text
    • http://creativetechno.in/userfiles/file/16955601288.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160d5c1cb9a780---27444020040.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/25264375782.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/11683255616.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16091b6509ab71---12066613543.pdfIn PDF document text
    • http://barnesfamilyconnection.com/clients/f/f3/f37d50667a1bb99e511e26172889fab9/File/15116170891.pdfIn PDF document text
    • https://davaocarrental.com/images/file/65725309800.pdfIn PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/tamowugivodixavem.pdfIn PDF document text
    • https://chambres-hotes-aube-bleue.fr/userfiles/file/siwowurawujewozumabep.pdfIn PDF document text
    • https://varbackaforskola.se/ckfinder/userfiles/files/619315321.pdfIn PDF document text
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/8qt4ap2id90rdgol97s32tc091/getodadexiboxosuw.pdfIn PDF document text
    • https://charlesstreetvideo.com/userfiles/file/98466395585.pdfIn PDF document text
    • https://mgogs.com/mgfiles/file/69725306825.pdfIn PDF document text
    • https://muachungbaohiem.com/uploads/userfiles/file/dobijaxufofodorubuve.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/bivsl2p5s46p7q977ookughtd7/22350107001.pdfIn PDF document text
    • http://orderkai.com/uploads/files/77525719294.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/sazow.pdfIn PDF document text
    • https://fultoys.com/userfiles/kadidakonepusijaz.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/62578038666.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/sokisawo.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_off0000f664.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF664 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010e7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E7B 10512 bytes
SHA-256: 68b0d91cbada65ab78d1a7124a1b829b0f38799264393a395d1bd4a4c9b49e06
font_02_sfnt_off00012655.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12655 17608 bytes
SHA-256: 6d4ef341104baaa10ca04e223dcfb2c09d04e5d76ec852938b5f9ab8fe83c14f