Malicious PDF — malware analysis report

Static analysis result for SHA-256 387c3d8367fc2374…

MALICIOUS

PDF

75.9 KB Created: 2021-09-10 18:16:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a5b1bad49226e9915175ee2be531d84a SHA-1: 013fc098de307aea0f37c7b5001fb29e08292022 SHA-256: 387c3d8367fc23741fe75d147d14def7db5943de2acf3fc90eff3d4e0b4adf49
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm designed to redirect users to potentially harmful content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights this behavior, indicating a tactic to obscure the true destination or distribute malware through a network of sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://digbijoynath.in/uploads/userfiles/files/vowikojuvatudaziv.pdf In PDF document text
    • http://evolution-dev.com/file_media/file_image/file/ruwekeletowokimipeba.pdfIn PDF document text
    • https://wedding-photos.cz/userfiles/file/36388149802.pdfIn PDF document text
    • https://k31szmq42-nu28.com/contents/files/53738782656.pdfIn PDF document text
    • https://theelementrama9.com/userfiles/files/zugifudivakedufunazo.pdfIn PDF document text
    • http://globalsublimation.net/uploadfile/files/22159225428.pdfIn PDF document text
    • http://5thaveseniors.org/userfiles/file/14675521222.pdfIn PDF document text
    • http://shinhwajudan.com/userData/board/file/48133468451.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/0n9l666v5f18qgkg7m7svckl65/32171248822.pdfIn PDF document text
    • https://limadelimon.com/images/file/funibe.pdfIn PDF document text
    • http://zenithmetals.com/files/jenalenoxi.pdfIn PDF document text
    • https://www.aicsmindia.org/ckfinder/userfiles/files/samesewikofiwuj.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/nowegovonu.pdfIn PDF document text
    • https://ferropula.hr/files/73555027307.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/12849865956.pdfIn PDF document text
    • https://vienhung.com/webroot/img/files/3299371392.pdfIn PDF document text
    • https://tpijobportal.com/ckeditor/ckfinder/userfiles/files/zafujus.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16135bb5bdc26c---siwilevediwexuzusug.pdfIn PDF document text
    • http://chinahongji.com/d/files/zibegowulatu.pdfIn PDF document text
    • http://precisao.org/files/files/kosopazimubevod.pdfIn PDF document text
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/78873080015.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=snaptube+free+video+and+music+downloaderPDF 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_off0000c32e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC32E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB40 17424 bytes
SHA-256: fe7840f448bacd72b7fbcc54841dac1f43c32eec30c7ca3b363e097a0154eaeb
font_02_sfnt_off0001081e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1081E 11248 bytes
SHA-256: bf5ccb37f627fc12ee7b2d992f66302afc094d96724e64fb95f151beb62e7879