Malicious PDF — malware analysis report

Static analysis result for SHA-256 61fb517931b72087…

MALICIOUS

PDF

77.8 KB Created: 2021-09-03 18:54:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ac7b9d3ab09cccf859699c82bdce33d2 SHA-1: eff7e25603a4d7e6f2ad2d947e61c1eb33e4caa4 SHA-256: 61fb517931b720876d5407f7372dc5df08f2b3de346057cb21edbed046b4773c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the PDF functions as a link farm, directing users to multiple compromised websites and potentially disposable hosting. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://coretry.ru/uplcv?utm_term=sharp+refrigerator+service+manual PDF link annotation
    • http://boschvietnam.vn/files/usersfiles/files/41626759308.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bbf31578201---xizagifodezatexo.pdfIn PDF document text
    • http://alternatifmedikal.com/img/userfiles/files/71861846633.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/nasosimaworavatuvenunulan.pdfIn PDF document text
    • http://mtreurope.com/ckfinder/userfiles/files/donifafufelidavob.pdfIn PDF document text
    • https://nibrasimansch.com/userfiles/files/1013086627.pdfIn PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca7efe5936---97299171048.pdfIn PDF document text
    • https://raovat72.vn/uploads/news_file/32767207971.pdfIn PDF document text
    • http://jezirka-biobazeny.cz/UserFiles/File/13450797504.pdfIn PDF document text
    • http://blackivy.pl/userfiles/file/sewuwenevafotiz.pdfIn PDF document text
    • http://grafiport.com/userfiles/file/nasoxobawaxani.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/tifokezenepi.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/3rr84ge9rs3j58bp3jf59711fi/35106115921.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/f1a77224aa56bc6722a27de16f14dd08/45555263665.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/84798609056.pdfIn PDF document text
    • http://www.siphonicflowmandiri.com/upload/files/foluzuturesolidokixobik.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b069352e0f4---91168829958.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c0799af2dab---46636042213.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/retipadimajimozenemafilej.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/funapelegikagodel.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/xadewepikamumifofel.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/cc5ded5ab191f2ae80943d9b0ca7d1de/mexenezotug.pdfIn PDF document text
    • http://geasit.it/userfiles/files/48133095825.pdfIn PDF document text
    • 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_off0000cb1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e335.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE335 11168 bytes
SHA-256: cdc874233e70a167d9fda81cf1c31b49865132e58190e2fa8b9e0532171197cc
font_02_sfnt_off0000fd2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2B 17168 bytes
SHA-256: 29e94f54cfc5650f3c6f65e70eab431c5bf8128218c4cf56172ff5d37cf0f116