Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c8cceec21c6b313…

MALICIOUS

PDF

79.3 KB Created: 2021-09-11 21:59:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7f4f41d815aedb7522b49e658df1200b SHA-1: d4b9f4e0a08cbf91c01452e1747bc72de8b86598 SHA-256: 7c8cceec21c6b3138c0eb938539cc74af73ad15cd7cd25d2492c8c2bc92e5957
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects to external URLs, as suggested by the PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics, which are often used for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 https://spotiverify.com/ci/userfiles/files/36589401571.pdf
    • https://hiddencliff.kr/FileData/ckfinder/files/20210910_3BD7960992F9B892.pdf
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/topapopak.pdf
    • http://nhatnamvina.vn/rich_editor/file/56118106493.pdf
    • https://damsindia.org/admin/uploads/file/lapatewamimatefew.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca68c0e636---zitikulijod.pdf
    • http://travellightnepal.com/userfiles/file/50290912119.pdf
    • https://gites-les-bardots.com/userfiles/file/88801565524.pdf
    • http://ksnjl.com/userfiles/files/97992211471.pdf
    • http://esllearningbydesign.com/app/webroot/files/file/49754683650.pdf
    • http://daisin1977.com/js/upload/files/28666859986.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135866791478.pdf
    • http://park-seversk.ru/other/js/ckfinder/userfiles/files/luzufoditafe.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137aa051c096---lotef.pdf
    • http://sov.tranovice.org/webpagebuilder/ckfinder/userfiles/files/fudukusibotokebav.pdf
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/dimojagujigipaminitusat.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/2459a7960bbb6c2031791294e9e55e51/12774097678.pdf
    • http://intelekt.biz/uploads/pages/files/7066400010.pdf
    • http://fcraregistration.com/UploadedData/file/purifotedubonazuguximadoz.pdf
    • http://farmina.ru/uploads/files/31253059118.pdf
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/84554183739.pdf
    • http://takramaipai.com/mypicture/file/zetidevisudipufote.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=mini+militia+doodle+army+2+god+mod+apk
    • 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_off0000cf71.bin
0cc2b776a3b5d874a09e67ae64bb54d82a276098b151f69166ac3ca9ba72d90a
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF71 18328 bytes
font_01_sfnt_off0000fe8a.bin
5ed9352823a47e191da10ab69f8a8a7beb3b684c23feff1ac5394a1706d93d5e
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE8A 10888 bytes
font_02_sfnt_off0001177e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1177E 16792 bytes