Malicious PDF — malware analysis report

Static analysis result for SHA-256 88bb34344300b469…

MALICIOUS

PDF

70.9 KB Created: 2021-09-03 06:52:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e64002327c00be554cf8e03a9e4d9e40 SHA-1: e92e06402931f10a1e0bfd47b97fd73ac1a5d479 SHA-256: 88bb34344300b4696c96001d2b5d5b67ae4b9ee166e6fb15c331d14236349c56
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and extensive URL usage suggest it's designed to lead users to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://queure.ru/uplcv?utm_term=operation+of+municipal+wastewater+treatment+plants+manual+of+practice+11 PDF link annotation
    • https://airflow-skateboards.com/userfiles/files/7930992647.pdfIn PDF document text
    • http://burragebrothers.org/demo/jolie/beta/userfiles/files/visobakobaraxiwokusinarup.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210703011412651353mapngxni2s68.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/376d511f2d46cdae840e3d11b4d60093/mukomulabid.pdfIn PDF document text
    • https://familienarbeit3plus.ch/userfiles/files/nigomajukiguxasaw.pdfIn PDF document text
    • https://namphuctourist.com/userfiles/file/99487791652.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/96946786475.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/tp2isepjcefgc9jlongstb7eui/25621753872.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///28455373557.pdfIn PDF document text
    • http://canvangdientu.com/images/file/wokerugiw.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160895b0da5c49---21510757989.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa81192bafe---dedamu.pdfIn PDF document text
    • http://marathon-gexin.com/Uploadfiles/files/21843298549.pdfIn PDF document text
    • https://interior-mark.com/ckfinder/userfiles/files/gukizirurasisi.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/966d383dd5b83747d763af0cf513fde0/zaxejesafiv.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4c0aec85e---doderazulatudirifakito.pdfIn PDF document text
    • https://premiersuli.hu/files/files/24403421374.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607892f576942---80220753754.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a17e339ee6a---rozugepivogotulogefirodes.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160812741af7b9---89421810469.pdfIn PDF document text
    • http://alltechsro.cz/files/86793852053.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///202105306598_365523651.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_off0000b4e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ccf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCF4 15536 bytes
SHA-256: b4e71a2d4ed704c9a1794705449b14588af840530bd0d537d70d62d7cc429923
font_02_sfnt_off0000f3f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F0 10904 bytes
SHA-256: c6e44d898348fc81395e2f0b76a5662eb8c0ef8786c32d91b6be3cbc7d7ffe22