Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c22d7b77aa803d1…

MALICIOUS

PDF

80.4 KB Created: 2021-09-22 13:02:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 57a7afc3faf7527061e2a6bc28c8a881 SHA-1: 1b7ca4f41790fb102ee63997f8c6c9925a198f74 SHA-256: 4c22d7b77aa803d15355843b123e09983e0890a3dfe2c6f6662d36d1a2f77aac
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The embedded JavaScript is likely used to facilitate the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=use+phone+as+nfc+key PDF link annotation
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/risikevotij.pdfIn PDF document text
    • https://biographiewerkstatt-singer.de/userfiles/file/82863376862.pdfIn PDF document text
    • http://teakdeck.pl/files/file/937323653.pdfIn PDF document text
    • http://wildpflanzen-planung.de/file/22541118901.pdfIn PDF document text
    • https://cmf8.ir/data/file/zabone.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613decd5b70bc---52105591585.pdfIn PDF document text
    • https://clarkfamilybuilders.com/home/clark/public_html/ckfinder/userfiles/files/bebatuzatomuvapusetip.pdfIn PDF document text
    • http://kerrya.com/ckfinder/userfiles/files/7937388287.pdfIn PDF document text
    • http://h04ydivan.ru/userfiles/file/94270974475.pdfIn PDF document text
    • https://stka.gr/ckfinder/userfiles/files/magemiwiru.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/zegaruja.pdfIn PDF document text
    • https://rafautama.com/uploads/file/xumobepomadimekug.pdfIn PDF document text
    • https://episcopiaoradiei.ro/files/visozifotivebotusalimoj.pdfIn PDF document text
    • http://tvkinter.com/file_media/file_image/file/36421467334.pdfIn PDF document text
    • http://vencedor.coop/images/admin/file/vererivaje.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/pezaterafuzomebuwe.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/92121529921.pdfIn PDF document text
    • http://zhatuogz.com/uploadfile/file/ponav.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/32864850875.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/xeralakuvovarifaba.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/98406419286.pdfIn PDF document text
    • http://www.firstpages.eu/app/webroot/files/userfiles/files/84339088857.pdfIn PDF document text
    • http://carscaso.com/js/upload/files/dezabelem.pdfIn PDF document text
    • http://feuerwehrobrigheim.de/upload/files/12499837428.pdfIn PDF document text
    • http://polkovnik.su/upload/file/venemavesalamapotipipax.pdfIn PDF document text
    • http://mwcapital.net/ckfinder/userfiles/files/labobure.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_off0000d739.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD739 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF50 10456 bytes
SHA-256: 02629f13bc8f21183166e78ca9b0be48a62b8b2c4bf83d33fa1e339efdc39364
font_02_sfnt_off0001070b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1070B 17400 bytes
SHA-256: 8d3c02823a47ca5da14abcc4860dfdb429147885778a5b2a10249c7f0faa2872