Malicious PDF — malware analysis report

Static analysis result for SHA-256 88c4385253e42743…

MALICIOUS

PDF

89.2 KB Created: 2021-07-14 07:11:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 801d29e10c8540c7f2fc82dd817e7708 SHA-1: 489d6ca59e0638e71bebdb49b80090f07bca4899 SHA-256: 88c4385253e42743e34fb6cbc211944a891143be79addf39d6cb166ea321114a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm structure, suggesting the document's primary purpose is to redirect users to malicious sites. The embedded JavaScript likely facilitates this redirection or further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://hitecds.com/userfiles/file/vezonurozodalovoz.pdf In PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/11ba59af4d43798e026558f109d402b3/44670575503.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/9tivjs33mh4q3huqo9lk54hg59/nogebosusa.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/97625507261.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/fq433tvuptis9u7s9kb22dad04/gurigupipasigeliletunezuk.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/726f37aa6459b5d88d470fb2eb4d8078/sojijufiragarupikari.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/918hrebncjm50090tri6niq3f4/77662789568.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc75bc8981---didinera.pdfIn PDF document text
    • http://sns.hu/_user/file/guvev.pdfIn PDF document text
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/fubororodinefiveloko.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a08b25281e7---gazekamibivuvinexovuvexa.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/70cd43912406ea0e4bde66377333e537/figugebumuzojevizutug.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/vajevolodixoliz.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/727bdd4e4ec6a910ab3c24a301df1f18/57080957227.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/jegar.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160795ace83543---70539182773.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/46666011095.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab0c38c4ee7---31062324377.pdfIn PDF document text
    • https://paperland.bg/uploads/file/namikik.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5860ea4c80---buzoxobuxuv.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb46c0722e---gulazixupikiriv.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/96622059825.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/d76d8cc2dfd45a60cfc06e058d5dfe2c/mufifugivizixeguzipex.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082e15d7fe8f---6975245608.pdfIn PDF document text
    • https://anukulagrotech.com/ci/userfiles/files/muzetez.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=most+comfortable+humidityPDF 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_off0000f7e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7E1 17648 bytes
SHA-256: 8ad8b38785f4be83bdeaa2259bf8397d1f9a8ae7fa5b7ed625b76817733ef406
font_01_sfnt_off000125fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013e14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E14 10984 bytes
SHA-256: d3d40eec155748ab6d6b908f4cda611bed9d064311f0815b2c76f2cf8ba07cdd