Malicious PDF — malware analysis report

Static analysis result for SHA-256 921745c44dd31828…

MALICIOUS

PDF

72.2 KB Created: 2021-09-15 12:09:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a10685cfb87ab51d1b9ff5efd69f7ce1 SHA-1: 15045a1579cd8e05d66ccf5fce29697f66318e6c SHA-256: 921745c44dd31828b42be9948dca4b0051eacbabce9c5640245181d2787ef4b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The presence of multiple external URI heuristics and link farm indicators strongly suggests a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://thic.net/plugin/ce1/ckfinder/userfiles/files/77846999451.pdf In PDF document text
    • https://mandarinusa.com/userfiles/file/1630975627.pdfIn PDF document text
    • http://hoclaixebinhthuan.com/upload/contentFile/file/lujere.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/252886e8e16b56b266de9caee9aa897c/dotutefigu.pdfIn PDF document text
    • http://flashdisplay.net/UploadFiles/FCKeditor/20210912141414.pdfIn PDF document text
    • http://clinical-pain.com/pds/userfiles/files/jevatapewiso.pdfIn PDF document text
    • http://texmet.pl/userimages/file/xozixujosunudogopajozete.pdfIn PDF document text
    • http://fbrasil.com/userfiles/file///mabolagewifavipixagid.pdfIn PDF document text
    • http://pomodorolennep.de/gfx/userfiles/files/wumonavarep.pdfIn PDF document text
    • http://banner-ever.com/ckImg/files/82749374974.pdfIn PDF document text
    • http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/73922202256.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/bp527pggvlvsnpu896tlc5g2ae/dasojexitaxitebeb.pdfIn PDF document text
    • http://colorfulmedia.de/fotki/fotki/file/52540043185.pdfIn PDF document text
    • https://stillwaiting.org/userfiles/file/14610993643.pdfIn PDF document text
    • http://aptwash.com/userData/ebizro_board/file/51540573376.pdfIn PDF document text
    • http://www.satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/45749919824.pdfIn PDF document text
    • https://newsru.md/upload/userfiles/files/61463430751.pdfIn PDF document text
    • http://atletika-pardubice.cz/files/file/10554646101.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210907_909B2C6F12693B6A.pdfIn PDF document text
    • http://ratchee.com/ckfinder/userfiles/files/63666476859.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/8690c9d751c4ef4b8521dafcac912b13/91386620557.pdfIn PDF document text
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30212264965.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=i+love+you+in+different+fonts+copy+and+pastePDF 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_off0000b7e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7E4 10844 bytes
SHA-256: b1ddf2efdc9cdf04ba609f384e6c92a43318edb3717d0ab4149967277884eed7
font_01_sfnt_off0000d119.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD119 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e92b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE92B 16180 bytes
SHA-256: 638aab0ab9569a9a465b985e7bfd1a2eafb6d6f5e6ab8931b7daf152ebaf857c