Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb9e37a8e52a80c4…

MALICIOUS

PDF

79.7 KB Created: 2021-09-19 11:12:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2a3af4c7850e4db69ca2503cf44666c3 SHA-1: 1fe822f84964c036c487147a83a6e5447f717d88 SHA-256: bb9e37a8e52a80c4a867d5c5e6879fbd38c93bbee6fc04e101dcb2eb0de459f1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and a significant number of external URIs, many of which point to compromised CMS uploads and disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript likely facilitates the redirection or exploitation process.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://moje-stranky.eu/userfiles/file/javibijotikipipuz.pdf In PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba5de4a868---57421308509.pdfIn PDF document text
    • http://duhochoangthanh.com/upload/files/79368808641.pdfIn PDF document text
    • https://sardiniagreencoast.com/userfiles/file/buwunowelaxirijosifuven.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/b909779b54b4cc305a8feb988b24d361/masadediwojudu.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/39257273731.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/15056940867.pdfIn PDF document text
    • http://express-service-auto.fr/ckeditor/ckfinder/userfiles/files/87803387594.pdfIn PDF document text
    • http://wawa757.com/uploads/files/77536872706.pdfIn PDF document text
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/58183239867.pdfIn PDF document text
    • http://safetyassessmentsolutions.co.uk/ckfinder/userfiles/files/39067726577.pdfIn PDF document text
    • https://www.premiumtrade.ro/ckfinder/userfiles/files/jinino.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/jemetewodizibigem.pdfIn PDF document text
    • http://snieznik.pl/userfiles/file/zolafareb.pdfIn PDF document text
    • http://ssanadia.in/userfiles/file/tizinurigukotofod.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/damedipugexinabinasix.pdfIn PDF document text
    • http://wagnerpc.com/userfiles/files/19729489436.pdfIn PDF document text
    • http://gaishachuukobuhin.com/js/upload/files/96411811571.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/mk1qj37urm1n774jm493ns44ba/787802996.pdfIn PDF document text
    • https://caror.hu/ckfinder/userfiles/files/tudogufalakola.pdfIn PDF document text
    • https://tsydesign.com/userfiles/jws/files/buxebuli.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=player%27s+handbook+5e+pdf+download+freePDF link annotation
    • 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_off0000d1a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e9b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B2 17588 bytes
SHA-256: a0ac52796eddcee1624495da539b5f9cfc7ce658d68135a1edb047f5cfdae74d
font_02_sfnt_off0001172e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1172E 11008 bytes
SHA-256: 3355eb07eb47b05c9987b9b78844879402c804454d53aa136af2f2e99f8a5e70