Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dda51bcd47d9b3b…

MALICIOUS

PDF

83.9 KB Created: 2021-09-20 09:51:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 17194aaeb3d7c2c4143824c7ae885b8f SHA-1: 58dcf2aa7960be77561bc0267f80b978d65c9db4 SHA-256: 8dda51bcd47d9b3b54d64bb980c3ed1b9362633a23fd5b7178a92755a48f0b2a
166 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier. The 'SE_CLICKFIX' heuristic indicates a social engineering attack that instructs the user to press Win+R or paste a command into a terminal, a common tactic to bypass macro restrictions and execute arbitrary code. The embedded URLs likely serve as lures or download locations for secondary payloads. No scripts were extracted, but the PDF structure and heuristics suggest an attempt to exploit user interaction.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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://huntic.ru/uplcv?utm_term=how+to+make+server+in+minecraft+android PDF link annotation
    • http://taiwan-tsai.com/upload/files/fazupunoxudamokefurit.pdfIn PDF document text
    • http://ukwoodrecycling.com/userfiles/files/dunedidifujujewojirotefa.pdfIn PDF document text
    • http://askaudit.ru/price/jadojokovok.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/5562730077.pdfIn PDF document text
    • https://tekstilkentrehber.com/upload/ckfinder/files/kasifusub.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///mudasekekifomaxatiki.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/mokubasuji.pdfIn PDF document text
    • http://sevgineslianaokulu.com/ckfinder/core/connector/php/uploads/files/53244168487.pdfIn PDF document text
    • http://gdwtechnology.com/fckeditor/file/24127752668.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/66144291096.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/49008780884.pdfIn PDF document text
    • https://daks-96.com/f/uploads/files/68831593801.pdfIn PDF document text
    • http://shceping.com/upFile/photos/2021-9/file/68415644755.pdfIn PDF document text
    • http://ural-resyrs.ru/data/file/72887151920.pdfIn PDF document text
    • https://yuktogel.com/contents/files/japifaxirawoj.pdfIn PDF document text
    • https://marblo.ph/app/webroot/img/files/wixas.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/tigozufazago.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/62449153605.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/tawodaxegirepaxozemuke.pdfIn PDF document text
    • http://davcpundri.com/css/file/97116634910.pdfIn PDF document text
    • http://clairvoyantinfotech.com/demo/images/zexipazefojigubotonowe.pdfIn PDF document text
    • https://betsin.org/userfiles/files/jenajetikijifefigidexi.pdfIn PDF document text
    • https://premium-house.uz/images/file/11990830863.pdfIn PDF document text
    • http://ridendo.cz/files/file/lezufedemuguzoxirejejare.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/161368e7ff1248---lorinesosegunekafema.pdfIn PDF document text
    • 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_off0000e032.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE032 18736 bytes
SHA-256: 248fd4c0fa77faafaf3da421ea1cec5c147c946c4ad850e2e69090cd3262f46f
font_01_sfnt_off00011081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11081 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012898.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12898 10828 bytes
SHA-256: 62e8116b53a1d4bc77a43dd3f3f6f032206d04dc76fa9615095ba9b67241481d