Malicious PDF — malware analysis report

Static analysis result for SHA-256 d31d91a2f70ce4fb…

MALICIOUS

PDF

71.1 KB Created: 2021-09-28 15:53:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 73cfb7e635bca8777744b5184cc0ff67 SHA-1: 4200c71fc391107061988ca0b8422e9d87043621 SHA-256: d31d91a2f70ce4fb4f78cbe0572d94165b46c0208e39d5571379c417c5e6fdfb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code or redirecting users. The numerous external URIs, many pointing to compromised or disposable hosting, suggest a link farm designed to obscure the ultimate destination, likely a phishing or malware download site. ClamAV and ML classifiers strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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.
  • 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.
  • 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://rebizplus.com/userfiles/file/88559903670.pdf
    • http://dasbluemchen.com/kaxusof.pdf
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/59a577242dfbcf60659c29cacd67256e/bawetojuforawijexisi.pdf
    • http://bcslaw.hu/admin/fck_upload/file/bevukegik.pdf
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/vavaduw.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d19428bec5---52354288974.pdf
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/55413980237.pdf
    • http://jplus-ag.com/upload/files/BodyFile__6152135CD15B1.pdf
    • http://apexnepaltravel.com/userfiles/file/67227541504.pdf
    • http://hoangnampte.vn/quangbasanpham/app/webroot/upload/image/files/gulavokejobugoro.pdf
    • https://ceylanotel.com/firma/files/texuzeg.pdf
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/7581b912d83b9f5b8d091295bec8ffe1/96440556879.pdf
    • http://www.taimaobi.com/admin/ckfinder/userfiles/files/suzotesowaxonogasig.pdf
    • https://www.hemingway.bg/app/templates/js/ckfinder/userfiles/files/82048792369.pdf
    • http://owv-sad.de/userfiles/files/xekenijijofit.pdf
    • https://sardavetri.it/userfiles/file/nogifufop.pdf
    • http://maimungkorn.com/UserFiles/file/70473863222.pdf
    • http://weiken-rc.com/upload/files/7467915811.pdf
    • https://menokatea.com/ckfinder/userfiles/files/podasedigabebiviji.pdf
    • https://associazionemusicaviva.it/uploads/file/ratisilisobobaxujitij.pdf
    • http://darangyi.com/userData/board/file/39444231944.pdf
    • http://dallard.fr/ressource/site-image/files/wifarukewatanew.pdf
    • http://tilestone-pools.com/i/File/6252020742.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/f540cf6947ed90595960fba6ebe6fedd/laxedopowezuturope.pdf
    • http://nghieuphong.com/upload/files/jozoxakiwa.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=tubemate+download+free+2020
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b4d0.bin
a40ba9b5bbfd3ed603ed1026ce51fcdda2069563aa565207d7e2b275aacb4e5b
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4D0 15836 bytes
font_01_sfnt_off0000dda9.bin
fce1470ff7de3fd065f5e09be349b893d30a1791b0171594d721190cade659f9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA9 10788 bytes
font_02_sfnt_off0000f69a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF69A 16792 bytes