Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e13452a089e3901…

MALICIOUS

PDF

81.9 KB Created: 2021-09-19 06:08:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ce562c9c255671a28b91f57297b610d0 SHA-1: e7603d44899c90c72c80bd8e266e098ffce5acf2 SHA-256: 4e13452a089e39018541f3e9784d2f17da44ba80a29025445bb84911696a49dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these links. The PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristic specifically highlights the use of compromised WordPress sites for hosting content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://highendschmiede.de/highendfiles/file/vexitupujinolejal.pdf In PDF document text
    • http://hylimusic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/51303211272.pdfIn PDF document text
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/gorolisumafezoferoro.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/76693343477.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/95408142231.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/29485297841.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/4275586542d08c6eaf11cbe6ffba71db/kamosikasafixojojados.pdfIn PDF document text
    • https://fulzugaskozpont.hu/files/xeguwosekuvitefenavoj.pdfIn PDF document text
    • http://www.polni.si/Images/files/tesaluf.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/zosugaxu.pdfIn PDF document text
    • https://lockerova.eu/admin/upload/documents/66204935299.pdfIn PDF document text
    • http://cokhitienvuong.com/uploads/files/7668283247.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/161405db088237---84932389801.pdfIn PDF document text
    • https://doublehair.center/upload/ckfinder/files/58758950561.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a706339f2c---viguredo.pdfIn PDF document text
    • http://membranekeyboard.pl/_data/file/55024553136.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/97400356574.pdfIn PDF document text
    • http://zapatosperezcabrera.com/ckfinder/userfiles/files/diramim.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614653852a8c7---78727205325.pdfIn PDF document text
    • http://www.culturehousesun.org/photos/file/pagemawedan.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16140f398c5bb0---jukixina.pdfIn PDF document text
    • http://ijfbn.com/editor_up/pofigaterabenera.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/99226929430.pdfIn PDF document text
    • http://e-district.org/userfiles/file/38710324569.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=easy+tube+video+downloaderPDF 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_off0000db0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB0C 18076 bytes
SHA-256: 1c24a88bec9d85eacfcc5fe3150061c07d3cdf1ad530049033df2ba9580d6281
font_01_sfnt_off00010966.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10966 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001217d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1217D 10732 bytes
SHA-256: 620269ce8ac25846765b72c4750641275c69dc76cd18ca8618b7d13fce737062