Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1e5b4c138718296…

MALICIOUS

PDF

81.7 KB Created: 2021-09-12 16:13:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: aa567f077f6bc41a274e5429ca6e5582 SHA-1: f3ec07567a4b0cf1867178b381f457bd539c1929 SHA-256: b1e5b4c1387182964d31a2b988dfa9ca597c07625362593659d26bdedf7eb09c
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple links to potentially compromised sites suggests an attempt to exploit user trust or deliver malicious content through various vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ketdoanbus.com/webroot/img/files/88281517651.pdf In PDF document text
    • http://ptaki.info/imgekoprojekty/files/89476219221.pdfIn PDF document text
    • http://langmypham.com/luutru/files/fadewajepaluvezukazozo.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/34246983180.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/47468141794.pdfIn PDF document text
    • http://chipublichouse.com/ckfinder/userfiles/files/67218737475.pdfIn PDF document text
    • http://sugarfree-gelato.com/upload/file/41023989692.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/45d7d9c78ed163e6db77fa49fe15e69a/38558874309.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/48857235330.pdfIn PDF document text
    • http://studiotrusso.it/userfiles/files/gizobebif.pdfIn PDF document text
    • https://holcom-wd.com/webroot/img/files/mivojifilexunojokogolute.pdfIn PDF document text
    • https://birutelorasin.com/contents/files/salufudefovapepagunututim.pdfIn PDF document text
    • https://healthlantern.com/ckeditor/ckfinder/userfiles/files/dipeluledufosobi.pdfIn PDF document text
    • http://mnogonomerov.ru/uploads/file/vedimenuxes.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/fejabiveridovuket.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134857eccc81---bikujedukur.pdfIn PDF document text
    • http://pb-book.com/user_file/file/43635056431.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/f06feab14e1e76f66666606b6ed03d66/85200132969.pdfIn PDF document text
    • https://doktor-ara.com/userfiles/files/26196444517.pdfIn PDF document text
    • http://www.ssc-ras.ru/ckfinder/userfiles/files/sejorelirejegezosiw.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/82718196315.pdfIn PDF document text
    • http://feg.vn/uploads/files/24242711692.pdfIn PDF document text
    • http://artc-polymers.com/upload/images/files/36839703731.pdfIn PDF document text
    • https://ceccarmehedinti.ro/userfiles/file/20063910237.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=download+video+fast+and+furious+8+full+movie+mp4PDF 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_off0000d852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD852 17656 bytes
SHA-256: ef3f8c9750eb04d531f8f93daa688d76fecbf6094f61a569bbfba697c648e068
font_01_sfnt_off00010612.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10612 11196 bytes
SHA-256: c012df6c7a98f79fcecb814560f25bb599dd3dedfab348426b0918e0e09fe035
font_02_sfnt_off0001205a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1