Malicious PDF — malware analysis report

Static analysis result for SHA-256 a27e9bfa6cbc4215…

MALICIOUS

PDF

89.6 KB Created: 2021-09-01 16:02:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 61492787037def146546cd51e05f8134 SHA-1: 47503f1fb91487d3dae9a92d70dbf906fc1401aa SHA-256: a27e9bfa6cbc42153857aed091e6037cc7f681d41e81c4917492a6bd7098f038
204 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript and multiple external URIs, many of which point to compromised CMS uploads or disposable hosting. The heuristic 'SE_BROWSER_INSTALL_LURE' indicates the document likely prompts the user to install a fake browser extension or update. The embedded JavaScript is likely used to facilitate this social engineering tactic, potentially leading to the download of a second-stage payload. ClamAV detection further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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 https://allytemp.ru/uplcv?utm_term=meaning+of+the+word+inadvertently
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/76f0c75d77194cfa22f93364c5baa198/87838856692.pdf
    • http://ageddfjtjgrade.pretty-match.com/upload/files/12502912143.pdf
    • http://nuestratierrapremios.com/campannas/file/91537547893.pdf
    • http://ahzycw.com/upload_fck/file/2021-8-14/20210814213627452930.pdf
    • http://designpavelzapletal.cz/files/file/runuzuzerona.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5724cbd07f---4826448187.pdf
    • http://thaimassagemodel.com/ckfinder/userfiles/files/99625477710.pdf
    • https://shipnhanh247.vn/asset/files/niwizuxekuxiga.pdf
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085887acccf7---lonilibeneg.pdf
    • http://annassteen.com/ckfinder/userfiles/files/saxeriwe.pdf
    • http://sbstroy53.ru/img/files/pumeradimupafudekam.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16080c8e9ab21f---zezefobejunevobamuniselux.pdf
    • http://nagakuratrading.com/js/upload/files/legiretonilelusefaluxezag.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/d57fd6c28fe0adb2836d329939b1754e/82419159856.pdf
    • http://malachowiacy.pl/files/file/47286310461.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16125eb99a455b---28198063927.pdf
    • https://ijtm.in/userfiles/file/wokunidijutiwajudokuren.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16094c8ed68f2b---luzezixefakibiloduwur.pdf
    • https://chatsystem.site/js/ckfinder/userfiles/files/39309388147.pdf
    • https://silverlabpupsforsale.com/userfiles/files/vedivigudonir.pdf
    • http://thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/15726318057.pdf
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/8a7c2f6bba5ee2209fa768ff0bb66f36/38641585037.pdf
    • http://king-ber.com/UploadFiles/file/20210810120915848.pdf
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/1c0c6961931f9987cc121fccebfca0f5/82116191262.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160afa0efab448---82083794899.pdf
    • 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_off0000f5d0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D0 16792 bytes
font_01_sfnt_off00010de2.bin
005f4f74dde4906d705cde219cff3e6918665e8eafc796e0c1d6ef7f3e38b511
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DE2 18960 bytes
font_02_sfnt_off00013ee8.bin
7c58072073567dee6873b9d6ab09925820fd4a01025c55e30ba6281b24852525
pdf-font-stream PDF embedded font (sfnt) at offset 0x13EE8 10724 bytes