Malicious PDF — malware analysis report

Static analysis result for SHA-256 de18da867a723485…

MALICIOUS

PDF

73.1 KB Created: 2021-09-19 19:12:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8dd2b4e4f1c5974ce0743c584b94df49 SHA-1: e5d2a51568d23c0c3554e12dbffc7e8a8892b5da SHA-256: de18da867a72348590caf6e103597009bfd1d0b0d771a7d0897187233642a49f
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the presence of numerous external URIs and links pointing to potentially compromised or disposable hosting, suggesting a phishing or malware distribution attempt. The document body is unreadable, but the PDF structure and URL analysis strongly suggest a malicious intent to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://onsale.social-push.cc/data/fckeditor/files/52327074510.pdf In PDF document text
    • https://htijsr.com/userfiles/file/sazolexineto.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/29393062376.pdfIn PDF document text
    • http://alptw.com/images/files/gerut.pdfIn PDF document text
    • https://anandamsanyal.com/userfiles/file/ligunadatanitila.pdfIn PDF document text
    • http://grandioso.asia/editor_upload_image/file/buxumaxupo.pdfIn PDF document text
    • https://agencement-menuiserie-var.fr/stockages/files/64803216563.pdfIn PDF document text
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/xuzitexikisuz.pdfIn PDF document text
    • https://abandassociates.com/ckfinder/userfiles/files/38666087701.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/f2547539b2bf430d35bde2a1fe9e6488/22101424636.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130afb471c66---48361801218.pdfIn PDF document text
    • http://kozszemle.hu/uploads/files/vobuwowaverelabul.pdfIn PDF document text
    • http://dges.in/userfiles/file/fajalewuvomajer.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/nojewe.pdfIn PDF document text
    • http://wangguanhardware.com/userfiles/file/vuturez.pdfIn PDF document text
    • http://ryukatsu.com/userData/board/file/gunavagiza.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/878f63dab5a67a0b1dcd34aad7714bf0/rugamurajanevoninoxasij.pdfIn PDF document text
    • https://spotiverify.com/ci/userfiles/files/ruxewenonofewofom.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/7b02b90067bcdbcd9fe2e119cb932fb1/duwuvebinusakojitilize.pdfIn PDF document text
    • http://danchrisjewelry.com/userfiles/file/16507079405.pdfIn PDF document text
    • https://nezrenweb.com/calisma2/files/uploads/2456085744.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/13261157412.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210911190339860.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=among+us+mode+menu+apkPDF 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_off0000bde6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5FD 10572 bytes
SHA-256: 1bff38734ba2480be8ec19dba62583e609886e7c67884a2a2ce8e0a7dd0de550
font_02_sfnt_off0000edef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDEF 15972 bytes
SHA-256: 17735ac00cc84ff4052fc13b7916986733a1feffea268e8b6613ba307cfa6b51