Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e43f818e838cf4a…

MALICIOUS

PDF

95.8 KB Created: 2021-09-18 02:04:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 1c5f1e3282066e0bbe84b2177d0c253f SHA-1: c72693781ad833353caad37cc3e7702528840e5f SHA-256: 3e43f818e838cf4a9742b2e7439cb58c4bac5a34c46ba0d1c49d79ba6de82a70
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://dbjadow.pl/attachments/file/dowoxisem.pdf In PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/85456013254.pdfIn PDF document text
    • http://cctsw.net/whly/up_files/FCK/file/20210904_222811_189.pdfIn PDF document text
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/40272922450.pdfIn PDF document text
    • https://tomorrowhubs.com/upload/users/files/59420118075.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131db052b307---65799334905.pdfIn PDF document text
    • http://15449010.com/FileData/ckfinder/files/20210914_050FAF4FBE7086D4.pdfIn PDF document text
    • http://www.focitabor.hu/userfiles/file/192358653.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/livex.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/7307520968.pdfIn PDF document text
    • https://www.privathospitaletkollund.com/ckfinder/userfiles/files/88005917707.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/gediwadisitoranuzenu.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ede085ed77---fupod.pdfIn PDF document text
    • https://0800-707-808.com/upload/ckfinder_temp/files/20210916072758.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/36605167438.pdfIn PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/zejarulurozo.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613e02829d1b3---7282349577.pdfIn PDF document text
    • https://rimi.sk/userfiles/file/30562139484.pdfIn PDF document text
    • http://machi-tomo.xyz/js/ckfinder/userfiles/files/rugelogaxix.pdfIn PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/fogaz.pdfIn PDF document text
    • https://kawanmto.org/contents/files/5146646105.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=drag+racer+v3+full+screenPDF 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_off00011145.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11145 10540 bytes
SHA-256: 8e6a219dab947e20e36619d4d138e73f62013da360ee96e7e3ab5792fbda6e82
font_01_sfnt_off00012987.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12987 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014199.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14199 18664 bytes
SHA-256: bf76136e0dea635e1ac5240577192cc73801fc2a1564d8c950464089d2a8e965