Malicious PDF — malware analysis report

Static analysis result for SHA-256 21926e307d6d90a5…

MALICIOUS

PDF

79.9 KB Created: 2021-09-10 20:45:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 401abd76dc28cc3a7e98082a1adb79ac SHA-1: 73f9101402b2bd4e0d0c24c2613e2e87c241a16d SHA-256: 21926e307d6d90a55e9cc272cb7520c41522bdbdd3eb32fd12243d53e673950a
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to suspicious PDF files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm on disposable hosting, suggesting an attempt to obscure the true malicious destination. The embedded JavaScript likely facilitates the download or execution of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://piazzademarini3ge.com/userfiles/files/wupuzakuxat.pdf In PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210905_8E683363EB06E026.pdfIn PDF document text
    • https://eltonltd.ru/sites/default/files/uploads/zakulibi.pdfIn PDF document text
    • http://agilesolutions.in/uploads/kagopup.pdfIn PDF document text
    • https://artenika.pl/fck/file/49081743696.pdfIn PDF document text
    • https://ww150005.linebot.net/upfile/files/20210902230045.pdfIn PDF document text
    • http://palami.by/images/file/48779901290.pdfIn PDF document text
    • http://client.diffuse.info/files/lomavowozukojimubatewek.pdfIn PDF document text
    • http://hzzxtl.com/UploadFile/file/20210908040624644.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/ditugigafilutozeres.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/80392675534.pdfIn PDF document text
    • http://techsystem.gr/data/uploads/ckeditor/files/80116780335.pdfIn PDF document text
    • http://1137.jp/app/webroot/js/ckfinder/userfiles/files/97838870147.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/nuxenefosirozomu.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/60713851035.pdfIn PDF document text
    • http://dooroc.com/tk/upload/file/77586601211.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/tikilabigodotulepob.pdfIn PDF document text
    • http://muaah.ca/userfiles/files/95601769283.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/wowepiwilomumulakajow.pdfIn PDF document text
    • https://0a3exp.com/upfiles/editor/files/zepufawivokolafivowu.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1613452b05ceb9---sosaxuf.pdfIn PDF document text
    • http://nhakhoasaigonkimcuong.com/uploads/images/files/xupunovekukuviratawawifov.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=vpn+master+free+vpn+%26+security+unblock+proxyPDF 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_off0000d295.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD295 18448 bytes
SHA-256: 466f524d9ba776f2f76e4be081e51f3833ffc2d8d5ce0560e193877de0f3e59d
font_01_sfnt_off0001030e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1030E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B25 10296 bytes
SHA-256: 42b7c40f19888a4b588445f6b544253b97fd042ebe08fd69633c81a5f0d2efbc