Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6810db1998ce7ea…

MALICIOUS

PDF

101.9 KB Created: 2021-09-06 04:17:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 63b5d0f41f4fdb204c95e6093b121cfd SHA-1: 285dad2a36bf97751c583a524b7bf35a3bea0a30 SHA-256: c6810db1998ce7eaccfc01fae43ebd596241620e507e8dbce028d21dd4fefabf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is a PDF containing a large number of embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate maliciousness, classifying it as a phishing trojan. The primary attack pattern involves luring users to click on these links, which likely lead to phishing sites or further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://innovatepc.com/userfiles/file/75260856746.pdf In PDF document text
    • https://www.nvsrolko.org/ckfinder/userfiles/files/23614931904.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/sizirifomotu.pdfIn PDF document text
    • http://eaas-journal.org/survey/userfiles/files/80310428083.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c915566186---dudisezesilemawu.pdfIn PDF document text
    • http://cyclad.org/UserFiles/file/99065958107.pdfIn PDF document text
    • http://janatalnajaf.com/basefile/janatalnajafcom/files/29634924544.pdfIn PDF document text
    • http://remaining-mc.de/userfiles/file/vepumotigik.pdfIn PDF document text
    • https://smartstone.ca/userfiles/files/nozikafuve.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/waxukagijawopam.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/29p5m39k6258vn0tcpu1bttm6d/gedasofamepefoka.pdfIn PDF document text
    • https://yar-net.ru/userfiles/file/86662178640.pdfIn PDF document text
    • http://2478.ru/admin/ckfinder/userfiles/files/13515773462.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/34359467449.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/5k4lvj3bmk7ovoag6dt94rv5u1/jesiwale.pdfIn PDF document text
    • http://law885995.com/upload/fckimages/file/batanagulumekajegudegu.pdfIn PDF document text
    • https://cryptobasics.biz/uploads/files/bulonaru.pdfIn PDF document text
    • http://rilta.net/userfiles/files/pepopakimofora.pdfIn PDF document text
    • https://arredamentigiacobbe.it/file/35792660386.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/ckfinder/userfiles/files/sesuvimewatavejafupume.pdfIn PDF document text
    • https://lazerom.pro/media/file/kasux.pdfIn PDF document text
    • http://kemmurad.com/webroot/img/files/33758454622.pdfIn PDF document text
    • http://www.sun-green.eu/ckfinder/userfiles/files/dibasifapirasixotun.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/73184378707.pdfIn PDF document text
    • http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/7086158112.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1607c75889f19f---38953597119.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/16a0408482d2035b76ceaa111c6e913c/6679058636.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=fillossera+della+vite+pdfPDF 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_off00012904.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12904 10428 bytes
SHA-256: d8406c1f418826cedf9e8ab34fdec8c19a6dbe86dff0386d1f146c6f34c5619a
font_01_sfnt_off000140c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140C4 18200 bytes
SHA-256: af42ea16224c1dadedde7b6a0ada739bc5540859b6a0eff8e4da390c67f2c1d8
font_02_sfnt_off000170eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x170EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1