Malicious PDF — malware analysis report

Static analysis result for SHA-256 38e1a6d69563f44e…

MALICIOUS

PDF

69.9 KB Created: 2021-10-03 00:53:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 527afa26c812473c643d5766d844a48e SHA-1: 5df27a122013ce4d0adfa234dee490efcd0078a3 SHA-256: 38e1a6d69563f44ee088e18b98e8c3d9ce825ba152971b099f6272959dd9cf74
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic suggest the document is designed to redirect users to potentially harmful websites. No scripts were extracted, but the overall structure and heuristic firings point towards a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

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 http://mytrangroup.com/uploads/userfiles/file/52549135135.pdf In PDF document text
    • https://hobbypet.cz/files/file/suzojor.pdfIn PDF document text
    • http://rurisnet.org/images/file/36235269627.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/3304205691.pdfIn PDF document text
    • http://farmandari-sarvestan.ir/images/news/files/41243903935.pdfIn PDF document text
    • https://rosedreamholidayhomes.com/ckfinder/userfiles/files/16905558959.pdfIn PDF document text
    • https://n-vv.dk/userfiles/file/44008958976.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/gafusitilonarezi.pdfIn PDF document text
    • http://muntepa.com/userfiles/files/mumawoziveseditabulome.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/5v7814vhu9v7349meiu176hik8/bujitatejax.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/cf269e61d8033a39e6fa19486b5cc78e/17960643496.pdfIn PDF document text
    • http://antropolog.ru/userfiles/file/sulane.pdfIn PDF document text
    • http://tubesealer.com/uploaded/file/1020535306147cc1259270.pdfIn PDF document text
    • http://bsp-oblspl.org/ckfinder/userfiles/files/52272742131.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/91873827340.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/44362741882.pdfIn PDF document text
    • https://hometutorsdelhi.com/userfiles/files/67787242705.pdfIn PDF document text
    • http://lnaixi.com/userfiles/file/20210918001929_226924092.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/vubabujaweje.pdfIn PDF document text
    • https://leifs-auto.dk/images/file/77506746098.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/65481428032.pdfIn PDF document text
    • https://www.netcorp.hu/data/editorfile/24268941444.pdfIn PDF document text
    • http://levant-tekstil.com/other_files/File/55582550628.pdfIn PDF document text
    • http://vector-food.pl/userfiles/file/59615097450.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/jutaposu.pdfIn PDF document text
    • http://phdpecs.hu/userfiles/files/78823882353.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=beowulf+cluster+raspberry+piPDF 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_off0000b128.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB128 10864 bytes
SHA-256: 837c82489c2384337997f5e75a6b9baac0aca567b0e5689093d5de3cc5fe5b03
font_01_sfnt_off0000ca4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA4E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e260.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE260 15740 bytes
SHA-256: f03fb0f90f8d12c8d0862cd8a01fff4150c4ae6f7541e6385740d1c764c9e1b0