Malicious PDF — malware analysis report

Static analysis result for SHA-256 031e61cf99a1eb5e…

MALICIOUS

PDF

85.8 KB Created: 2021-09-18 21:22:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ead858b79622b2bacf1948bb9af53c4c SHA-1: 1b6cfceeb635a721dd1deb5e78e2d186667f30a4 SHA-256: 031e61cf99a1eb5e1a6e5d80d616fda9b9b379d4e18e28fa09d4227248d90b9f
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and a link farm pointing to compromised CMS uploads and disposable hosting suggests an attempt to lure users to malicious sites, likely for phishing or malware distribution. The primary attack vector appears to be a malicious attachment delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://swiftnb.com/ckfinder/userfiles/files/15505254624.pdf
    • http://okna-dvere-online.cz/media/upload/upload/file/78868475269.pdf
    • http://sintjorisparochie.nl/userfiles/file/xivumami.pdf
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/ladasolin.pdf
    • https://hk-delight.com/UploadFiles/file/53934477674.pdf
    • https://curewelldiabetes.com/userfiles/file/ludeguwuwilidume.pdf
    • https://successstudio.net/userfiles/file/65581986357.pdf
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc0ff4bb6e---zunawosokerobepevilimine.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2ed8ab3f9---mupikukokixew.pdf
    • http://www.vinoplaza.nl/img/upload/files/87562804932.pdf
    • http://chapraptti.org/userfiles/file/vebonuvafod.pdf
    • http://santiagoporter.com/js/ckfinder/core/connector/php/files/7592858362.pdf
    • http://edwindijk.nl/home/edijk/domains/edwindijk.nl/public_html/uploads/file/gegalixetekemen.pdf
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16133c67008616---48656637665.pdf
    • http://stelmart.ru/userfiles/file/venanavizofudav.pdf
    • http://siripanyalamphun.com/user_img/files/giragotanuxifaw.pdf
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1613a417029a7b---33776752118.pdf
    • http://becucci.it/userfiles/files/15189295369.pdf
    • http://keletunderground.hu/images/uploaded_pics/file/zizer.pdf
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc23165881---sogeka.pdf
    • http://insightonafrica.in/userfiles/file/boxigetoliwal.pdf
    • https://watfordfairtrade.org/app/webroot/img/files/dexikenifurepigaziruzime.pdf
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/34779319792.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/32rppa8hb88n2vkm337s03u8q7/33807387037.pdf
    • https://greenvalleykerala.com/ckfinder/userfiles/files/43155247104.pdf
    • http://www.valathors.com/ckfinder/userfiles/files/17188554012.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=alpine+quest+app+for+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e995.bin
5bf2d7c6c971a3ee663c7e62e466326cb09bd063d291c94f944102453bb1bb03
pdf-font-stream PDF embedded font (sfnt) at offset 0xE995 10716 bytes
font_01_sfnt_off0001021b.bin
9cb6d9a7e18f977032ecd9ac821a6f1746bb2ca4f53ee7b23f240f999d189fbd
pdf-font-stream PDF embedded font (sfnt) at offset 0x1021B 18140 bytes
font_02_sfnt_off00013154.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13154 16792 bytes