Malicious PDF — malware analysis report

Static analysis result for SHA-256 9562ce5dfb8550c8…

MALICIOUS

PDF

72.4 KB Created: 2021-09-09 05:58:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 435456426d98e6bfc3a49f50e3f6fc8c SHA-1: 4ee9a7eff3d9adfcf79a3b8df1738b905650715a SHA-256: 9562ce5dfb8550c832fd3fd5c7434684c8647d8b9c4bf0c2db0353f3004b10b0
164 Risk Score

Malware Insights

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

The sample is a PDF document containing embedded JavaScript, which is a common technique for delivering malicious content. The heuristics indicate that the PDF acts as a link farm, directing users to potentially compromised websites or disposable hosting. The embedded JavaScript likely facilitates the redirection to these external URLs, which are often used for phishing or distributing further malware. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://inwebjor.ru/uplcv?utm_term=how+to+get+pokecoins+without+buying+them PDF link annotation
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/161325ca739858---80621533958.pdfIn PDF document text
    • https://maffart-guy.com/userfiles/file/19249178928.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/33746422922.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/83995276408.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613833f3b8801---5637850726.pdfIn PDF document text
    • https://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/lizimir.pdfIn PDF document text
    • http://park-seversk.ru/other/js/ckfinder/userfiles/files/78843398348.pdfIn PDF document text
    • http://mashhadgardi724.ir/basefile/mashhadgardi724/files/96517100249.pdfIn PDF document text
    • http://newmob.it/userfiles/files/2721815750.pdfIn PDF document text
    • https://traffictkt.com/viking1/uploads/files/29790621406.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/39812920831.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/35169724845.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/11839596e3b291078cb722b1ee8a43c6/maruxe.pdfIn PDF document text
    • https://thepainter.asia/upload/files/1553002468.pdfIn PDF document text
    • http://pbpharm.com/upload/files/dukebededowalabukika.pdfIn PDF document text
    • https://remoteyourstaff.com/calisma2/files/uploads/50601505151.pdfIn PDF document text
    • http://jfe.hk/userfiles/wetuxubetul.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/26877891307.pdfIn PDF document text
    • https://wigs4less.net/nbloom/fckuploads/file/wajozopoti.pdfIn PDF document text
    • https://mokshadhamnepal.org/userfiles/files/meduvasurebitowepesavup.pdfIn PDF document text
    • https://bhandarisurgical.com/ckfinder/userfiles/files/18016090534.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/roxuzejamufubuj.pdfIn PDF document text
    • https://oriontradecom.com/ckfinder/userfiles/files/37686803958.pdfIn PDF document text
    • http://sattosushi.com/uploads/files/83282064182.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_off0000b60b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB60B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE22 11036 bytes
SHA-256: a7fe9fc3ab7520eeda355aa7435cb9fa305291ceb6ea61a9df691b94da21fa20
font_02_sfnt_off0000e77c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE77C 17300 bytes
SHA-256: b61198916e09ad08f3b4add8dec3f5f0fcd7cd59601fb7f1a3d1c971735ae96b