Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb6fed229c354bc4…

MALICIOUS

PDF

74.1 KB Created: 2021-09-18 09:02:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 03d82bc59c4057f502d1cf599ea4a700 SHA-1: abd8d54e9b445877f2c9cfa853d6eec592bb12aa SHA-256: cb6fed229c354bc451d12815efba3f2012628a2046f9973952aa66df7eef064c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content or phish users. The heuristic 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggests the intent to leverage compromised infrastructure for hosting malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://flexa.cz/docs/file/kaviketobapevejuvemivaxaw.pdf In PDF document text
    • http://alpha-th.com/userfiles/file/83243154616.pdfIn PDF document text
    • https://ecpa.fr/uploaded/file/fowifagelo.pdfIn PDF document text
    • http://phutungquanghieu.com/app/webroot/files/ckfinder/files/15143195532.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142eba418df7---12954581354.pdfIn PDF document text
    • http://thomas-zigon.de/images/file/gorivapaduneru.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/65775145631.pdfIn PDF document text
    • http://ridendo.cz/files/file/3011578448.pdfIn PDF document text
    • http://dywin.com/uploadfile/files/duwil.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/1614031f3b70a1---3786055321.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/30300b19d39c2af486d8fa413e278fd9/43106663798.pdfIn PDF document text
    • http://gmei.lt/ckfinder/userfiles/files/90297542481.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210915223133.pdfIn PDF document text
    • https://calendarsunrooms.com/userfiles/files/motexu.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613604b9be766---67387660611.pdfIn PDF document text
    • http://urgentcarepb.com/userfiles/file/roradogegab.pdfIn PDF document text
    • http://schokoladenbrunnen.de/idata/taputexaxusudodanelekelaw.pdfIn PDF document text
    • http://urotunisia.com/uploads/FCK_files/file/9022083808.pdfIn PDF document text
    • http://snft.ro/media/file/rofoxamonuvog.pdfIn PDF document text
    • https://fruitssupplier.com/app/webroot/img/files/gizefigev.pdfIn PDF document text
    • http://thephinhmienbac.com/upload/files/zuwodum.pdfIn PDF document text
    • https://soosekszer.hu/upload/files/gadosizal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=strike+force+kitty+3+hackedPDF 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_off0000bd85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d59c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD59C 10708 bytes
SHA-256: c4d5d28888ceaa3f10a5e810f7b746a56e3eccc3105ecb532c617056ae048e1a
font_02_sfnt_off0000ee69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE69 17472 bytes
SHA-256: 06e452e9c90b7830bafee1946208abeceab938d5c674e4486829d2b506d5877b