Malicious PDF — malware analysis report

Static analysis result for SHA-256 da0889af06d63f2b…

MALICIOUS

PDF

68.5 KB Created: 2021-09-16 18:52:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3f904446dfbaf02007c99627bb697934 SHA-1: 49742f83678d843292494d657f8b08b38c7fada4 SHA-256: da0889af06d63f2bd64e3e408b479423ddb239b0e338b615ab3c6e5ee11665f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple URLs extracted from the document point to various domains, many of which are hosted on potentially disposable or compromised CMS upload storage. The presence of these link farms suggests an attempt to obscure the final destination and potentially distribute phishing content or malware.

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 http://kunmobile.vn/files/uploaded/20210913/file/47519856774.pdf In PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/v7lla88bcvnk6da1be0m5d53f5/34650987870.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/42690395500.pdfIn PDF document text
    • http://ceomit.com/fckupload/file/jogexojixalabubo.pdfIn PDF document text
    • http://teranor.com/ckfinder/userfiles/files/pedopim.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb3fa2961c---36848230946.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/36160284774.pdfIn PDF document text
    • https://technoarc.net/userfiles/file/xamatavoxinijez.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/28381615774.pdfIn PDF document text
    • http://thaymanhinhlaptop.com/userfiles/file/40429762538.pdfIn PDF document text
    • http://dichvugiayphep.biz/upload/ck/files/83528734915.pdfIn PDF document text
    • http://siamsnail.com/media/userfiles/files/92440388395.pdfIn PDF document text
    • https://underworldgear.com/upload/users/files/xeviv.pdfIn PDF document text
    • http://tcsm62.org/uploads/news/file/12936350775.pdfIn PDF document text
    • http://wrtour.com/FileData/ckfinder/files/20210902_D8F3BA3F58673704.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/tonazenemitixaz.pdfIn PDF document text
    • http://weifong.tw/fckimages/file/jejubofusedaxup.pdfIn PDF document text
    • http://leadershipcareer.kr/fckeditor/_upload/file/kolikulu.pdfIn PDF document text
    • http://ieltsadd.ir/cache/fck_files/file/55159213705.pdfIn PDF document text
    • http://stluciachamber.org/uploadedImages/contentImg/file/jedezutuw.pdfIn PDF document text
    • https://photofetimages.com/sexaxuz.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/piwudexesalax.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/7005dfa70ee8066dcd1a914e52ccd4ec/zubepobajulolij.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/6c2ed830375aabaa4d3ab49592ecf40c/73953664324.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=fpsece+android+downloadPDF 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_off0000af75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF75 14732 bytes
SHA-256: f9d8045508cc7df4ebbfca0e80a340dc3e5fa752695021f9ed3698c11ad84117
font_01_sfnt_off0000d4c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C0 10472 bytes
SHA-256: 739c40d5a6519017fdf8072525e720d550989fc83995a5740edb56ae43d21390
font_02_sfnt_off0000ecac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1