Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ef92f3fffc92bbe…

MALICIOUS

PDF

68.6 KB Created: 2021-10-02 11:43:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: b2a379f1e807d9732b9d8f324c6b25f0 SHA-1: 66ea033e55e2704addc2d27ee7d43f270d010695 SHA-256: 3ef92f3fffc92bbe9158c46f13365a3321a3164e32f7c2080baf28ee9c184ee0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to suspicious domains and appear to be part of a link farm, a common tactic for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it is designed to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148e475c0518---87737673693.pdf In PDF document text
    • https://glycocalyx.nl/userfiles/image/file/bafatuvuwerefezuvakeje.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/2206264523.pdfIn PDF document text
    • https://rakbah.healthybitespk.com/alpha/ckfinder/userfiles/files/85492326498.pdfIn PDF document text
    • https://clifestyle.net/uploades/userfiles/file/59445146612.pdfIn PDF document text
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/23472832643.pdfIn PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/69598266449.pdfIn PDF document text
    • http://badaranquehablar.com/userfiles/files/55401540658.pdfIn PDF document text
    • http://geoscan.it/userfiles/files/47948694133.pdfIn PDF document text
    • http://kondicionery-lubertsy.ru/upload_picture/file/fafoxikuve.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/70902112393.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/87483334269.pdfIn PDF document text
    • https://iqrainternationalschool.org/_assets/files/95913855339.pdfIn PDF document text
    • http://www.gpkoaee.ru/ckfinder/userfiles/files/xapovuxugekune.pdfIn PDF document text
    • http://tfe-design.dk/userfiles/file/nazarimulewapukutigeven.pdfIn PDF document text
    • https://crcnueva.naturasoftware.com/uploads/images/files/47135893704.pdfIn PDF document text
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/nevisov.pdfIn PDF document text
    • http://iktoktatas.hu/files/file/30239501852.pdfIn PDF document text
    • https://100tmt.com/uploadimage/files/20210911190419.pdfIn PDF document text
    • http://skulpt.in/admin/uploads/file/45277280794.pdfIn PDF document text
    • https://diphong.com/uploads/49984269105.pdfIn PDF document text
    • http://tulga.ru/editor/files/janadutidoxokikirakarofif.pdfIn PDF document text
    • http://phongkhamthienhoa.vn/images/files/puvujemugofesotosu.pdfIn PDF document text
    • https://khyatiinfotech.biz/ckfinder/userfiles/files/49510456392.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=graphing+linear+equations+satPDF 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_off0000ad92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD92 15312 bytes
SHA-256: 8f71203c1822472f41f784b473755ef578bd702bda92e6b27ec1b8e391b12830
font_01_sfnt_off0000d40c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD40C 10816 bytes
SHA-256: 27d52c186aca180c81933a7b796132ba97a3126a76482755568aa3c2c4316293
font_02_sfnt_off0000eca1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1