Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4957b6d3de3b626…

MALICIOUS

PDF

70.4 KB Created: 2021-09-18 01:44:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a32db01f616afd10dba81bdce298e1d2 SHA-1: c72e8ac51df34fb18c315e9a3b0ffd8f0ac3a154 SHA-256: a4957b6d3de3b626ab161f38d943cc3da6c5ed80060ca71094ea4f70cd8f193e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, suggesting an attempt to redirect users to malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a strategy of using many links on potentially untrusted hosting. No scripts were extracted, but the overall structure and URL distribution strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://gibkrakow.pl/uploads/files/11890828986.pdf In PDF document text
    • https://vanchuyenduongsat.vn/upload/files/vewutolunezezurebaka.pdfIn PDF document text
    • http://homeopathyhk.com/files/gejazijelizigok.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/34197480974.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/7c03e0af992bf1fc9627019f81131ccb/bevadatuboxewitolamapasap.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109012127411438.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613739bec060b---23847457458.pdfIn PDF document text
    • http://imi.vc/upload/files/35590273931.pdfIn PDF document text
    • https://suksesunited.com/contents/files/raruzabipelufamifufadop.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/69715037173.pdfIn PDF document text
    • https://kede.org/userfiles/file/53049475694.pdfIn PDF document text
    • https://www.spitalmoldovanoua.ro/ckfinder/userfiles/files/48533715627.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/21775719464.pdfIn PDF document text
    • http://chunmianxian.com/upfolder/e/files/20210917184953.pdfIn PDF document text
    • https://kovtec.pl/eurostyl/photos/file/79284989229.pdfIn PDF document text
    • https://hanurichurch.org/ckfinder/userfiles/files/bexikejubovuwab.pdfIn PDF document text
    • https://actorconseil.com/files/file/3757782420.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/19795368182.pdfIn PDF document text
    • http://dermalab.pl/userfiles/file/98946174491.pdfIn PDF document text
    • http://tao-oita.com/admin/upload_filesfile/lemevet.pdfIn PDF document text
    • http://elcolono.net/userfiles/files/3157924355.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=elementary+statistics+pdf+answersPDF 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_off0000b385.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB385 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB97 15396 bytes
SHA-256: 132e6704418eb4f8b6ad80b1b2b10972ad265f2bf6f3c3d77a237e1c69b1d47a
font_02_sfnt_off0000f2ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2CA 10844 bytes
SHA-256: 257c05ff856dec167a0d40020ae19acc7926666889e8e663e201b8a9a5c8d221

Open this report in the interactive analyzer, or submit your own file for analysis.