Malicious PDF — malware analysis report

Static analysis result for SHA-256 87cb3193d0cb9e0b…

MALICIOUS

PDF

72.6 KB Created: 2021-09-24 12:44:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a8a93778ca2577ba1f672457f4623413 SHA-1: 0d5e61105ba96c4dacbf9959c3333f87f8957d35 SHA-256: 87cb3193d0cb9e0b28342f3903ad9cb747c165b1bad51abc7fec43b5e311a5a7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The presence of multiple PDF link farm heuristics and embedded URLs strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e9955e02ba---75211731354.pdf
    • http://marketingnews.fr/images/file/fitogozipajapeli.pdf
    • https://vietucmould.com/img-vietuc/files/75723346913.pdf
    • https://ciiinnovationsummit.com/ci/userfiles/files/gadofanuj.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/8876haf82754jqb0msvtqqm1vp/32143644995.pdf
    • http://raegcafe.com/uploads/files/8544798053.pdf
    • http://bernardthevenet.fr/ckfinder/userfiles/files/56731694243.pdf
    • http://sov.tranovice.cz/webpagebuilder/ckfinder/userfiles/files/nibenojaluv.pdf
    • https://milsagliksen.org/upload/ckfinder/files/79251524411.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131a8a1b98a4---45429435315.pdf
    • http://safarang.com/basefile/files/dapojipalozu.pdf
    • http://ciaooo.ru/uploades/userfiles/file/gidofanabebipu.pdf
    • https://cmf8.ir/data/file/lakelixigekenu.pdf
    • http://al-bandak.com/userfiles/file/53226851769.pdf
    • http://metabolizmusonline.hu/images/upload/file/61551174980.pdf
    • https://willmarareachamber.com/ckfinder/userfiles/files/tukowuwumufonabem.pdf
    • http://drumlockingclamp.com/FCK_Editor_Images/files/87542210057.pdf
    • https://iskoruma.com/upload/ckfinder/files/rawuvoberisetup.pdf
    • http://flamefitnessstudio.com/cewit/images/file/putesodivafolaromebojiju.pdf
    • http://shippingengineering.com/files/ckeditorothers/94275231191.pdf
    • http://cnmrobotics.com/files/files/74973086183.pdf
    • https://coevent.ru/upload/files/fisavumokefagebumerubug.pdf
    • https://kuwaitpolyurethane.com/ckfinder/userfiles/files/53804456575.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=move+photos+from+android+to+ipad
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b3b6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3B6 16792 bytes
font_01_sfnt_off0000cbc8.bin
777c9dcd3bdaba0e36681d247fc2db3f467d45eba8937cafb87bb924e617adda
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC8 19156 bytes
font_02_sfnt_off0000fc74.bin
4414e1a65555bda0398ddafb74139aba2742a90632b3827e004f9fc8c5eccb66
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC74 10776 bytes