Malicious PDF — malware analysis report

Static analysis result for SHA-256 82c1fba0eb8d8c56…

MALICIOUS

PDF

81.6 KB Created: 2021-08-07 10:48:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2f189b3783f95e686558f9f4081bed29 SHA-1: b138df41bd68e1606e9db9d3b6bad661f3b1e013 SHA-256: 82c1fba0eb8d8c56bddd24abc0f56b13a5313e6b7fe5f73eabafbb5d9b86ffd6
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160ab4f57a434b---povopakojodede.pdf In PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/c91c4e78c3558c64e099d2efe40ed988/sukeke.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/0e46rroivi2ma0r5kaaqtpajrm/zadukesulurevimusum.pdfIn PDF document text
    • http://habitat3.eu/userfiles/files/xilafewukujajoraxodun.pdfIn PDF document text
    • https://shiokerbau1.com/contents//files/51196464954.pdfIn PDF document text
    • http://tevukasveza.lt/ckfinder/userfiles/files/66726867241.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/84398610978.pdfIn PDF document text
    • https://sofupingame.com/calisma2/files/uploads/kigukevuxu.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/e6vn8ge8hpds58pa9ekf9u5flv/92474355249.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073d3a8cf7b9---pujeruxuxodu.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/f5f08fd3306f162bb55935b8322590ac/62228997633.pdfIn PDF document text
    • https://mygrind.ie/userfiles/file/pidaju.pdfIn PDF document text
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/6533389612.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/lelilimobasojojipofubaba.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/vk1i4q7tfsuia5gheebnn871rb/13096990617.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7a458b178---nexemivowuputagupusidukes.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/8b4e2d12983c38844a1e643395b679d5/zafenirijomepa.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/cba5f35719b36e6345ab7eca9fe22780/50513862040.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a14d27615d0---76860207219.pdfIn PDF document text
    • http://nhs1966reunion.com/clients/1/1c/1ca8f1639ee69cd7806809ed3bcda9bb/File/wipitesufolavotizel.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/24085732394.pdfIn PDF document text
    • http://dejede.com/userfiles/file/52199287535.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/rodezuwiwelifiru.pdfIn PDF document text
    • http://sakaryakasaplarodasi.org/userfiles/file/fuzanesakejivujazifekew.pdfIn PDF document text
    • http://mp-journal.com/media/file/58131014795.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=manual+pr%C3%A1ctico+de+oratoria+pdfPDF 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_off0000d721.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD721 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF33 18028 bytes
SHA-256: ed29126e8ca9c34b70df3f060c4c622b5305ec9a840f1e8b12ed1413f0842d71
font_02_sfnt_off00011d58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D58 10716 bytes
SHA-256: 938f7ed1f84cd69bd364d6c7d185419fd880e5e7d4ffa748ac24e8f41e116cdf