Malicious PDF — malware analysis report

Static analysis result for SHA-256 9535a2aeac21721c…

MALICIOUS

PDF

79.8 KB Created: 2021-09-17 08:07:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f89c4d50b2c58edc97752de8c3f67bd4 SHA-1: 45811962d95ed7f291e18f2258959c8cad9beba2 SHA-256: 9535a2aeac21721cbadf02004740feadee51b3a3aa632928045a942367a51d42
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to disposable domains, suggesting it functions as a link farm. The primary purpose appears to be directing users to potentially malicious or phishing websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://master-sign.ru/ckfinder/userfiles/files/15111552713.pdf In PDF document text
    • https://liantoong.com/archive/upload/files/5116027116.pdfIn PDF document text
    • http://kolaykanal.com/userfiles/files/17620528857.pdfIn PDF document text
    • http://aristosaigonhotel.vn/uploads/files/risufotolib.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/21068114580.pdfIn PDF document text
    • http://istvietnam.com/rich_editor/file/36452006654.pdfIn PDF document text
    • http://serextion2006.com/js/upload/files/62519859202.pdfIn PDF document text
    • http://stromzeleny.cz/file/55946741265.pdfIn PDF document text
    • http://zs-g.jp/app/webroot/js/ckfinder/userfiles/files/97800398488.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/zavomodowonewamisis.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/51876486473.pdfIn PDF document text
    • http://iweldbot.com/ckfinder/pho/files/87461286977.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/jitopugumogoguz.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109071744122189.pdfIn PDF document text
    • http://identik.hu/editor_up/kizinefikete.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/rituroko.pdfIn PDF document text
    • http://flairpens.ru/uploads/file/9134487979.pdfIn PDF document text
    • http://nextgenship.net/upload/file/2021090316307096555.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/2174080706.pdfIn PDF document text
    • http://terfigyelokamera.info/files/file/40645956150.pdfIn PDF document text
    • http://shinhwajudan.com/userData/board/file/75918271587.pdfIn PDF document text
    • http://myoffice2561.sesao33.net/UserFiles/File/35878346540.pdfIn PDF document text
    • https://nk-sostanj.si/files/file/jinanowewofuvibudisidigok.pdfIn PDF document text
    • http://www.sospapa24.com/lib/ckfinder/imgupload/files/taritoxedozomuzuxujasop.pdfIn PDF document text
    • http://gaongonmaiphuong.vn/webroot/img/files/92833834407.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=who+viewed+tiktok+profilePDF 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_off0000d603.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD603 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE15 16616 bytes
SHA-256: a17302c986ec6111390d10e28b520783a5367e5481d2a980dfbf7abd001622d7
font_02_sfnt_off00011964.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11964 10400 bytes
SHA-256: 2764ce67a5165de63e5ee01f2a1560362ff9a911636f3f1e8d2f3fcc9710bb29