Malicious PDF — malware analysis report

Static analysis result for SHA-256 5429b41b010cfc34…

MALICIOUS

PDF

74.3 KB Created: 2021-10-06 14:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: e7a2610da1d7a21004c41605f4e52153 SHA-1: 5d9fd8c7fb2ed829b88429ac771b0160d7a61cb6 SHA-256: 5429b41b010cfc34ea0553edceac5085a7fd78ccd758e1827efe7a67bafb3de2
104 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 websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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://interfacetravels.com/app/webroot/js/ckfinder/userfiles/files/fobanipofebob.pdf In PDF document text
    • http://tulga.ru/editor/files/62726156525.pdfIn PDF document text
    • http://clinicaveterinariasangiacomo.it/userfiles/files/jinabajomosivasemepev.pdfIn PDF document text
    • http://rfaaa.com/UploadFile/file/20210909071716974.pdfIn PDF document text
    • http://nessium.fr/userfiles/file/wikaforijexijinadefuk.pdfIn PDF document text
    • http://lica.plovdivweek.com/js/ckfinder/userfiles/files/dokalijipow.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1615a44cb11626---9241575795.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/126292026133891e7d125.pdfIn PDF document text
    • http://www.alcera.ca/userfiles/file/70920175560.pdfIn PDF document text
    • https://www.piramideidiomas.com/ckfinder/userfiles/files/7414851557.pdfIn PDF document text
    • https://gospel-streams.com/asset/ckfinder/userfiles/files/zinelifapomazezakusadezo.pdfIn PDF document text
    • http://decoworld.in/dayafter/uploadimages/newsimages/file/musetijirepa.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161559122dae68---59623325822.pdfIn PDF document text
    • http://gesundimjob.at/images/content/files/65509862278.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161475fe0d7fb8---61642286530.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/7renm5kr3i6pmkfjuak9pi06tu/3550041736.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/27139575379.pdfIn PDF document text
    • https://jvlegacyhomerepairsmd.com/nbloom/fckuploads/file/64390741476.pdfIn PDF document text
    • https://gtsk.solar-napkollektor.hu/js/ckfinder/userfiles/files/85224383566.pdfIn PDF document text
    • http://slbreakingnews.com/ckfinder/userfiles/files/90921815010.pdfIn PDF document text
    • https://bisleriuber.genefied.co/ckfinder/userfiles/files/polaxovopeg.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/bajudegivusanowijeziduge.pdfIn PDF document text
    • http://hondatayho.top/img-ngocbao/files/widegitokotoguwakowin.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109262252457775.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=minecraft+tokyo+ghoul+texture+packPDF 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_off0000b8da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d0f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0F1 10992 bytes
SHA-256: b2ca4cd005991f677af91ca7bf571f6b78d59c1d3d99b9fcab27fb3f44de6dd9
font_02_sfnt_off0000ea79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA79 18760 bytes
SHA-256: b73ceab6f4dddef369478bbfd7e4960d33336665e22c4c99dd71576774888a1c