Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4433bcc85db5c0d…

MALICIOUS

PDF

84.1 KB Created: 2021-09-10 05:20:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4998d7cfd3ce9e8b720054293426a828 SHA-1: a60f27f5880afadfe574961d441a4dbc797ff988 SHA-256: b4433bcc85db5c0db864fe4af8faee640cf4e018780ea037ba0eff6da23ae972
174 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external links, many pointing to disposable domains, which is characteristic of phishing or malware distribution. The 'Password-protected archive handoff' heuristic strongly suggests the document's purpose is to trick the user into downloading an encrypted payload. The ML classifier and ClamAV detection further confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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 http://risorsaterra.it/userfiles/files/77375427102.pdf In PDF document text
    • https://mayphoviet.com/media/ftp/file/59860543172.pdfIn PDF document text
    • http://eatatrudy.com/uploads/files/45647016002.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/88031521361.pdfIn PDF document text
    • https://solturism.ro/images/file/dupunonubozi.pdfIn PDF document text
    • http://sp3siemianowice.pl/userFiles/files/zidupid.pdfIn PDF document text
    • http://htwy.com/upload/file/bilozijodosatenimuwaju.pdfIn PDF document text
    • http://studioarclab.eu/userfiles/files/fomovedevadudoriwux.pdfIn PDF document text
    • http://lsmtrontractor.com/upfiles/file/20210908005255.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/22709440801.pdfIn PDF document text
    • https://kidneystonetreatment.in/userfiles/files/lefikameda.pdfIn PDF document text
    • http://flomojapan.com/upload/files/lavifexeki.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/23439710137.pdfIn PDF document text
    • http://idcla.net/upload/files/30484453035.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/161351a8d01b46---giperitekewemavulusogap.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/nowirigezawemixikeva.pdfIn PDF document text
    • http://oawebserver.com/piceditor/file/febeli.pdfIn PDF document text
    • https://www.ccs-corporation.com/ckfinder/userfiles/files/rawufosonosagaba.pdfIn PDF document text
    • http://hanstime.com/userData/board/file/gukoziluforutivuvis.pdfIn PDF document text
    • http://szsahsh.com/uploads/files/kibike.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/pipisarifuno.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/vumugugepiwegegi.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/496147225.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/81304cd92728f6fb9248ee5105778c24/13000705263.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=exe+file+converter+for+androidPDF 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_off0000e43e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE43E 17940 bytes
SHA-256: 06f988a33ab64a7b4532054af512799e36a13c6678ee08c40ed08b752fbca61e
font_01_sfnt_off0001129f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129F 10452 bytes
SHA-256: 7eafb38600882db59b4703b48eddd30ec304ee6e418d95b9294102f34e1cf500
font_02_sfnt_off00012a7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1