Malicious PDF — malware analysis report

Static analysis result for SHA-256 b066811a969c6083…

MALICIOUS

PDF

85.4 KB Created: 2021-09-14 07:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5ee367dd18ec5adb4d89a58607f5ba82 SHA-1: 4534cacb6308de753c6859a5f59482f2bf52cebf SHA-256: b066811a969c6083de6c07ff4606055e3bf1b6681e6b5fc38dc421cf10b757ce
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

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://chcial.ru/uplcv?utm_term=archos+70+internet+tablet+custom+rom PDF link annotation
    • http://shangrilayunnan.com/ckfinder/userfiles/files/88927025133.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/musegabedidufo.pdfIn PDF document text
    • http://www.llmhospital.com/www/js/ckfinder/userfiles/files/90832302536.pdfIn PDF document text
    • http://trust-law-firm.com/userfiles/file/20210911135104_1615389662.pdfIn PDF document text
    • https://alate.org/admin/fckeditor/editorfile/bijonowowudogojewekuwobed.pdfIn PDF document text
    • http://redemaisfarma.com/userfiles/file/67348226665.pdfIn PDF document text
    • http://nasfthr.com/userfiles/file/dogufoviwoxu.pdfIn PDF document text
    • http://unstitchedfootwear.net/files/file/nubulofudaxuxudamitexoxip.pdfIn PDF document text
    • http://hondasushi.com/uploads/files/80769753409.pdfIn PDF document text
    • https://fwstc.in/userfiles/file/44741889181.pdfIn PDF document text
    • http://marchmont.ru/imgs/file/56123730418.pdfIn PDF document text
    • http://3suntech.com/UploadFile/file/20210902123143366.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/wuwedalitinojumesi.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd286ad2b0---zigolimolifu.pdfIn PDF document text
    • http://turinimoti.com/assets/userfiles/file/87929767972.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/41962619649.pdfIn PDF document text
    • http://gruppocreta.com/userfiles/files/dejovokavax.pdfIn PDF document text
    • http://davobio.com/upload/files/83639690248.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/82831463222.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161344b8649cd6---56376105178.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/2kpmjf51j8c2fb5pmjh3agkpi9/46587158818.pdfIn PDF document text
    • http://azseal.net/uploads/userfiles/file/71066564231.pdfIn PDF document text
    • https://kovtec.pl/eurostyl/photos/file/rugalaminawu.pdfIn PDF document text
    • http://ayrh.internet-match.com/upload/files/54463498629.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_off0000e805.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE805 18612 bytes
SHA-256: 1b1e475f123682d339807321819377ec795ab68c291de48ffcc53e51c7e5f5b9
font_01_sfnt_off00011839.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11839 10888 bytes
SHA-256: 9a3cf1d0a76da7883424022051fa4c6a2cb8dcb5dc4c128ec5e2daff1a6f1fb0
font_02_sfnt_off00013149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13149 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1