Malicious PDF — malware analysis report

Static analysis result for SHA-256 857f2df490f567e6…

MALICIOUS

PDF

112.2 KB Created: 2021-06-02 19:01:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: fc4211b5cc66158a9369462c80253ac1 SHA-1: 992e025c0d5a7a8f6185e2bfa0921970539d5ab5 SHA-256: 857f2df490f567e6a758def5d76ba6c68585a6eb84b701fc50a3b54d1020b872
156 Risk Score

Malware Insights

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

The PDF file exhibits characteristics of a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/1608d0894b08bd---28677397883.pdf In PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16080fcaa1b267---74137432959.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606eee10c1110---48380247090.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608226bb3a780---32174286048.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1606cce9a69456---75032799862.pdfIn PDF document text
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/2ca74bfef1097bacd05a73400780209f/nasigojovib.pdfIn PDF document text
    • http://fenotropil.ru/userfiles/file/67367669536.pdfIn PDF document text
    • http://garderoba.sk/images/_file/wuvapazezumivola.pdfIn PDF document text
    • http://ttlh.vn/storage/ckfinder/files/lopafoluruwozexafuranove.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160895a560fe7a---juzixiv.pdfIn PDF document text
    • https://pharmnet.cz/ckfiles/files/files/26813435732.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/f8qoiucsm9urj9oq2ru52lb1gm/dosulezomugodujenol.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae3bd790f83---rimeradanimar.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1607038bc64ebe---mabunavago.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/kdcp5e8io3gs6a79c8r9tjuao4/85263466384.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609db44caaa0f---80157026462.pdfIn PDF document text
    • http://web68s.com/upload/files/54237457480.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/zMnd8XtcwSM/uplcv?utm_term=astro+boy+full+movie+in+tamil+dubbed+downloadPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013d71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D71 17464 bytes
SHA-256: 6ecc981e634dbc288d862d20cb156b57e8f5d2e7b77d3a4751f42f61ad9b1ec4
font_01_sfnt_off00017608.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17608 5436 bytes
SHA-256: 96e9320a07fb031dc953fa0e704e362bde7569e0a6e94b21a70b7d255f835c32
font_02_sfnt_off0001888d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1888D 12128 bytes
SHA-256: f23789732766ab59a0453482ea8a0ff5234a07658e5a4284291b33f10f5202f8