Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b024b60415ef7ed…

MALICIOUS

PDF

78.8 KB Created: 2021-09-22 16:20:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ecab568e4afe26239ecff2baab166f10 SHA-1: cfc14dd6a9d25c55ae08a66bd1c7956938519cb5 SHA-256: 7b024b60415ef7ed385da8d3853cfa25072e71239307874bdc1badecb0239fb2
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files hosted on various domains, many of which appear to be compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://corising.info/sa_upload/userfiles/file/20210917221017.pdf In PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/99651610008.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/78794953533.pdfIn PDF document text
    • https://equalitas.es/userfiles/file/tojuxoriromolemar.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/77648533011.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/1827865239.pdfIn PDF document text
    • https://protrialse.eu/files/files/89330652356.pdfIn PDF document text
    • http://dbexpertise.fr/catalogue_dynamique/file/wazakuwazarujulomilizunam.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/2e3fecd99e4367332be9f7ab86d6fab1/73663434106.pdfIn PDF document text
    • https://bya-ingenieria.com/ckfinder/userfiles/files/94178294183.pdfIn PDF document text
    • http://climtech.com/files/files/983152561.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/72130916366.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/tujujuf.pdfIn PDF document text
    • http://supermarketdv.ru/files/file/65358310563.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/vizen.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fce50c99d0---pelonoxigujapufami.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147435409ddf---9273975967.pdfIn PDF document text
    • https://liftsystems.ro/LiftFiles/file/jezipoduzogapukubigo.pdfIn PDF document text
    • http://valserve.in/web/k/main_admin/ckfinder/userfiles/files/kixusikafuwigolod.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/gilovamoke.pdfIn PDF document text
    • https://byocamacho.com/ckfinder/userfiles/files/72650400269.pdfIn PDF document text
    • http://sinoorchids.com/image/file/25386665023.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=venom+free+full+movie+onlinePDF 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_off0000d3bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3BF 17076 bytes
SHA-256: 7e3a4c8ab66ff5d5b696193fde72e78696ab971281c1f6bd853b1f15f596b061
font_01_sfnt_off0000ff89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF89 10080 bytes
SHA-256: c53959ccd8bc23d135049d57c24e263c63a9db43cc3b4ed258b4e7b7ed661757
font_02_sfnt_off000115ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1