Malicious PDF — malware analysis report

Static analysis result for SHA-256 c25cec4c1d734b70…

MALICIOUS

PDF

73.2 KB Created: 2021-09-09 17:07:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 338f5627440159c47367eb8d0dd18966 SHA-1: 522da83b3828589e6399b9b8f4bd9a6d5cbeeb2e SHA-256: c25cec4c1d734b70d2cd7559cb09e7b3cda33cc294820da36999ab9b5d9ab46c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were directly extracted, the nature of the links and the PDF structure suggest it may exploit PDF vulnerabilities or embed malicious JavaScript to facilitate further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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.
  • 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://chiangmaicharmingtravel.com/ckfinder/userfiles/files/55090280840.pdf In PDF document text
    • http://kristiankutschera.de/userfiles/file/31925006308.pdfIn PDF document text
    • http://domplus.su/userfiles/files/70712648002.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/wosuxalodivo.pdfIn PDF document text
    • http://solar-makernavi.com/ckfinder/userfiles/files/74266203111.pdfIn PDF document text
    • http://scpt.it/userfiles/files/80681998759.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/7df8cd83047176d2d79e7fffcced106e/larotilolizoziluvarom.pdfIn PDF document text
    • https://atasuorganiktarim.com/upload/ckfinder/files/1324650044.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/85478839963.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/febexere.pdfIn PDF document text
    • http://bon-mar.com/fck_user_files/file/muvogujexuz.pdfIn PDF document text
    • https://eastmanllc.net/ckfinder/userfiles/files/97222742916.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134707113f79---98373525935.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/54057831421.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/bdd46b973f636b020bb9bf69bcc832c7/18829654210.pdfIn PDF document text
    • http://baugeraeteverleih.de/benutzerdateien/pejaliguperirakep.pdfIn PDF document text
    • http://partner-support.net/user_data/userfiles/files/10680801814.pdfIn PDF document text
    • http://escalierdurire.fr/ckfinder/userfiles/files/panejomaxuvujozonesawez.pdfIn PDF document text
    • http://moristas.com/userfiles/files/26850221484.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/kuwaredomajofulivifire.pdfIn PDF document text
    • http://topup-fight.com/ckfinder/userfiles/files/30262595816.pdfIn PDF document text
    • http://agro-norwa.pl/userfiles/file/67701640891.pdfIn PDF document text
    • https://protum.se/file/93073557412.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+boost+mobile+internet+speedPDF 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_off0000b9d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1E9 17412 bytes
SHA-256: ff6307e4af98a5c1f69a5f8bf76d62267c30d0400ff8691642dd73527298cff6
font_02_sfnt_off0000ff46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF46 10608 bytes
SHA-256: a8800a04936f843e0f70f9ee01148edc9fc9bdcc1365ea62a1f8c6c428c39f40