Malicious PDF — malware analysis report

Static analysis result for SHA-256 b01f3c443d0751d7…

MALICIOUS

PDF

89.7 KB Created: 2021-09-05 11:00:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: bdc7526a73a63dfc18ebdb16c9edf71b SHA-1: 20d58b45b791ead55c43015d1c66d21b551a90ec SHA-256: b01f3c443d0751d75d48b02f69ab6c1ed9a3d9ec361c87bcaeaa1bd99009727d
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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://cructi.ru/uplcv?utm_term=electrical+engineering+books+free+download+pdf+format PDF link annotation
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/49f05bb432ebba25ec13b2f05683fb23/ribesod.pdfIn PDF document text
    • http://bannermaul.com/userData/board/file/bafazajipepunefage.pdfIn PDF document text
    • http://naturallabs.de/userfiles/file/60713522951.pdfIn PDF document text
    • http://christmaslandint.com/userfiles/23725998367.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/36562034769.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/86936e605b8205b26fb1d1faf7f109cd/19265710252.pdfIn PDF document text
    • http://imaginove.eu/data/Files/22340266125.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a7984f1873---zupitas.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/80329017981.pdfIn PDF document text
    • http://clairerolo.com/userfiles/file/9269670751.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a01cf5dfebe---2255069270.pdfIn PDF document text
    • http://85560891.com/upfolder/e/files/20210821054849.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/rerawisokimitemutegi.pdfIn PDF document text
    • https://pacpartner.net/images_client//imagesfile/genobox.pdfIn PDF document text
    • http://zs-oilfieldequip.ru/d/files/xudepex.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/d4u5jf1abtlaskjsk2th5cbbeb/58049637048.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/39959262548.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/ae07355e024fe2514a124c7b630e0989/xomekag.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/13274ab3e5e9c244b9b4f596c30e77dc/nedenuraba.pdfIn PDF document text
    • https://nhachoxebus.com/upload/fck/file/basopuko.pdfIn PDF document text
    • http://eprdel.cz/userfiles/file/67648511831.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/fawej.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/goxefibezo.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/9d49dfed4408c1e82e23c7bbb9b8951b/82267201085.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609452a88d44c---57765649263.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_off0000f597.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF597 11264 bytes
SHA-256: e06f903a990a79b4b57656dc90d601c7d25a11118ea6eb8a620663e9d3321bb3
font_01_sfnt_off00010fa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA0 18824 bytes
SHA-256: 36a2acfc4a3e8d493365efa530e118a73a2bbb22465f7e190c7c131d2067b695
font_02_sfnt_off0001405e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1405E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1