Malicious PDF — malware analysis report

Static analysis result for SHA-256 527f03c0dcc5ef99…

MALICIOUS

PDF

76.7 KB Created: 2021-06-22 12:59:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 311617de11d03ed50d7cb5448324f7b5 SHA-1: 5c531927abaffdb41909d688bae40d39a688e4bd SHA-256: 527f03c0dcc5ef99ecc7377952c1dacecc582c71100539b5aa083a8a0a7dc588
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://dcoderesearch.com/uploads/mejimasosabirodabirudagu.pdf In PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/1e4e414beaa29b6ffc96e3feee5625e3/79627830729.pdfIn PDF document text
    • http://toyotarent.tw/FileData/ckfinder/files/20210618_EF0BC19D2A21A74A.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160aff8e3dc2a9---vofisogigik.pdfIn PDF document text
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/5qrs4ia8j73c84r5jmsr5ikut5/wapoxetafe.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/n3lsu6fli1ad4mflkcp7c7qg83/jopasawiteponibavawuzav.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/rsim2df5d3272kc1r42l73ao83/tuwezoteponegekur.pdfIn PDF document text
    • https://planet-for-events.de/userfiles/file/laxojijigonitukut.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/ogkmuufdbq1kqsboi3uojbk268/26103005596.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/fexizufosawulokago.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/dvfiraoqr3se60hjfgdgm2lgbs/makizoguwusukufeminivufib.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608af9638b9df---kefonilovoxijetovuwixosa.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/kupekogara.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607bfdeb5f1b6---54349186618.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=facetime+calling+appsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE96 5112 bytes
SHA-256: e94e61ac3cfcf8638e0c65955a7ec91e29df92de774ce47ad30209ebe90912ea
font_01_sfnt_off0000fff2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFF2 11384 bytes
SHA-256: f2c167802d3af23df2f08a40725a019c641e23ed1883354ad2c5e13b08b2efa0