Malicious PDF — malware analysis report

Static analysis result for SHA-256 719187f7f82c4079…

MALICIOUS

PDF

80.7 KB Created: 2021-09-18 01:26:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 35205890d5cb92e967d99d5bfdb5d9aa SHA-1: 90e2c4cff797365920e9cd44297804967d4799a6 SHA-256: 719187f7f82c40798526ba6bb33e8f0c8ca9c7fc5fb5e223698db58cb276fd88
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which point to potentially compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. No scripts were extracted, but the overall structure points to a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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.
  • 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://0575zl.com/userfiles/file/53103254152.pdf In PDF document text
    • https://orderpoet.com/ckfinder/userfiles/files/70586999726.pdfIn PDF document text
    • http://demkapi.com/resimler/files/34077001133.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/61156907727.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/38910025399.pdfIn PDF document text
    • https://izyskately.ru/foto/ck/files/verowabafazimonoken.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/25db82dd5bc88c303a0ce9a6d1f939f7/rabozav.pdfIn PDF document text
    • http://abworder.com/uploads/files/zunakekajuvewebuw.pdfIn PDF document text
    • http://chromowane.com/userfiles/file/juzexujad.pdfIn PDF document text
    • http://goodlack.cz/userfiles/file/7975716427.pdfIn PDF document text
    • http://olympiad-bigben.ru/ckfinder/userfiles/files/torekudukofosonibejufe.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210905_8D70E211AE353A8F.pdfIn PDF document text
    • https://artgallery.devctn.com/ckfinder/userfiles/files/42665608157.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139f10ed401b---25473753872.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/10167695260.pdfIn PDF document text
    • http://swhwsolution.it/ckeditor-ckfinder-integration/uploads/files/5625378027.pdfIn PDF document text
    • http://ukrkarta.ua/fckeditor/userfiles/file/febalelegusukujefanobobe.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613834dad7652---palimidenaletikazuk.pdfIn PDF document text
    • https://lanhcongnghiepthinhphat.com/upload/files/pumuponemonemonotasakuxot.pdfIn PDF document text
    • http://simp-q.ru/userfiles/file/15151536657.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=reward+code+for+8+ball+poolPDF 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_off0000d928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD928 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f13f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF13F 10628 bytes
SHA-256: 2abb06e3a80b3bc350bcd4991790a0b753b8a369716bb96f55aa9ee81631b007
font_02_sfnt_off00010982.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10982 16944 bytes
SHA-256: 2844caf865be10f3e315c0bc2c35f0f2fa299629377af0f549b33dbf19b04dae