Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5827d1fea007a10…

MALICIOUS

PDF

109.3 KB Created: 2021-07-15 12:36:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 8e348626456b7b515394f141a4b0f185 SHA-1: 35234c50ece6304bc0d8659948e004b808d23de8 SHA-256: b5827d1fea007a1001a582e32c1b887c70d47703c35686bb198a2a7a25974446
124 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to compromised WordPress upload directories and other disposable hosting. The ClamAV detection 'Pdf.Phishing.Trojan-d2528dad23a95d95-10044376-0' strongly suggests a phishing or trojan distribution intent. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics indicate.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.2756

Heuristics 5

  • 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
  • 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://dainichiji.com/upload_ckr/files/dapekokuzip.pdf In PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/cd491342399ee8e58d81497d96efbac2/42981052626.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/bda476e402a228d760c136ddb25a6ed6/38190573814.pdfIn PDF document text
    • http://limoride.net/gallery/file/67729245109.pdfIn PDF document text
    • https://gachbinhduong.com/upload/file/70742088673.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ed50eef06---jinegonejesobitodader.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/06/17/file/tagomuva.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c290381805f---pizafufulidure.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d4c6c57a9---rutiram.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/5da50a85a0b3af9b4303156dec11f875/15050446968.pdfIn PDF document text
    • https://viettrungson.com/media//Files/gojodajukudetirazevisexu.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ac579f0e148---nisigatobipifimolid.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/42783399196.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/od2nr84ma9jqjdajaqsiom7i2d/91706726839.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/soxasafa.pdfIn PDF document text
    • http://haohanlegend.com/Uploadfiles/files/xaxaluvidiludu.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/30344621518.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/191ab6189880f5e50b830774c1919ee7/86809570872.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/b0825d0caa2f6c97328404c68c3791b1/ridevubelesisezam.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/p2ripkha5dnpqgllhvhp7osv06/rejirefupalo.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b064c1e27d2---89623544030.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e937cb53ce9---44529115996.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c76c16e841---89697300801.pdfIn PDF document text
    • https://gancza-yacht.pl/userfiles/file/zagorutofawi.pdfIn PDF document text
    • http://short-story.ru/upload/file/wexag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=sly+fox+meaningPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013730.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13730 10484 bytes
SHA-256: c01221042b93cf5355d9b5ee51adfe697a7c7aaa97a61bcb1233aeedfe4f5987
font_01_sfnt_off00014f09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001671b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1671B 19696 bytes
SHA-256: bdbf1c707593ceee49519f3d29834dc43badaf1fe1b0461155217f7f2b7918c3
font_03_sfnt_off0001989b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1989B 17288 bytes
SHA-256: a423aad4ebc4668c131d066ed055f4c35949eb90af68fb90df718cd034006095