Malicious PDF — malware analysis report

Static analysis result for SHA-256 a632f9b0f6eb852a…

MALICIOUS

PDF

68.4 KB Created: 2021-09-23 17:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 91909866af68cb7c7ef8db379f8557a6 SHA-1: a9702ddbc0a3b26b3a8c6b011795af69c714d696 SHA-256: a632f9b0f6eb852a6f62197e02443abe98775b39bc6dd6b3f0f999515e9fee37
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it functions as a link farm pointing to compromised CMS uploads and disposable hosting. The embedded URLs, such as 'https://nomylo.ru/uplcv?utm_term=good+morning+shayari+zindagi', suggest a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly indicate malicious intent, likely involving redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://nomylo.ru/uplcv?utm_term=good+morning+shayari+zindagi PDF link annotation
    • https://alquimia.in/admin/fckeditor/editorfile/nexomanex.pdfIn PDF document text
    • https://airxps.com/userfiles/files/85664621459.pdfIn PDF document text
    • http://mrtowing.ca/Lawyers/userfiles/file/1405353108.pdfIn PDF document text
    • http://poaglasses.com/uploads/files/202109231303192816.pdfIn PDF document text
    • http://caratow.nl/userfiles/file/83877452500.pdfIn PDF document text
    • https://www.creativetalentnetwork.com/ckfinder/userfiles/files/penobujewawej.pdfIn PDF document text
    • https://mallarpurnaisuva.org/go/file/sudekabuzewutu.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/zodar.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a1c0bb138a---89238284971.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbc9ad86e6---48752852732.pdfIn PDF document text
    • http://hani-bee.com/userfiles/files/mivadajube.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1614307f5c290c---14917351735.pdfIn PDF document text
    • http://sure2trips.com/bot/ckfinder/uf/files/rufabikuj.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/nuvave.pdfIn PDF document text
    • http://www.galiantsolutions.com/emailimages/file/wakogawivulud.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/51461963103.pdfIn PDF document text
    • https://dynasty888.com/image/files/20210905_025004.pdfIn PDF document text
    • http://khunghinhdepphuctin.com/media/ftp/file/torugakiwuv.pdfIn PDF document text
    • http://kutscher-customs.de/gfx/userfiles/files/jifiwamuzowatekeze.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/79050301105.pdfIn PDF document text
    • http://bjbtrh.com/files/pic/file/5012946050.pdfIn PDF document text
    • http://jongauger.com/ckfinder/userfiles/files/tegolig.pdfIn PDF document text
    • http://eiak.org/upload/editor/files/7959705329.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306705545cc.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_off0000b087.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB087 10632 bytes
SHA-256: 9b1603eba7a0df5f72933622ac9ecc8bef6825c7973c0b0b9ca996489759ed80
font_01_sfnt_off0000c86f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC86F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE081 14288 bytes
SHA-256: 7a225b052785238e535b2d0fefe5888a315a7c85ff2dfdf58834cf62a1d4837c