Malicious PDF — malware analysis report

Static analysis result for SHA-256 037d767f3920674c…

MALICIOUS

PDF

90.3 KB Created: 2021-09-03 21:56:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8ee13a313b5bd0ff365d23512966d91f SHA-1: 06c3f659bc7d0a64badd5d166fe318d4d37ad3d1 SHA-256: 037d767f3920674c726a71f4e31b0d5bfb6995a409cfdb3814a76e43699647ec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ClamAV and an ML classifier. Static analysis revealed it functions as a link farm, with numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites. The primary purpose seems to be redirecting users to potentially malicious content, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://nomylo.ru/uplcv?utm_term=exercicios+nomenclatura+de+alcoois+pdf PDF link annotation
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/f830de4058b54a656840f8efbfe7d230/vepozizebivej.pdfIn PDF document text
    • http://waetsukai.jp/system/ckfinder/userfiles/files/13240786081.pdfIn PDF document text
    • https://ajambary.com/userfiles/file/nawuxekun.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/fedotojerufinidafusatumu.pdfIn PDF document text
    • http://cappellastudio.it/userfiles/files/58750944328.pdfIn PDF document text
    • http://indago-rovigo.it/userfiles/files/3880342398.pdfIn PDF document text
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/28699267563.pdfIn PDF document text
    • http://calhi1977.com/clients/879053/File/takegavolademamelumax.pdfIn PDF document text
    • https://www.sacda.org/wp-content/plugins/super-forms/uploads/php/files/9i2g802ihk7ba4qst7b0act0i3/55736935228.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/hgarifqh9cd68efk4u4titims2/33978758372.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/79101871184.pdfIn PDF document text
    • https://jetaime-shop.com/files/wexeximotan.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/58886917950.pdfIn PDF document text
    • http://celyroknaterase.sk/editor_uploads/system/files/22105929800.pdfIn PDF document text
    • https://tbsva.org/Upload/files/20210706133628.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/92603858590.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/63588620596.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/98429198170.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd1512c289---91401226634.pdfIn PDF document text
    • http://elisa5888.com/shopadmin/upload/files/kibuxe.pdfIn PDF document text
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/853330ef201164b3d4a692d2edc8788f/ferixotomexebojewagugi.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_off0000f556.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF556 10964 bytes
SHA-256: 3fbab9bd9758676e3d10ed80ae90682608d1689099af4a726037b04a9f97983f
font_01_sfnt_off00010ec8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000126da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126DA 20388 bytes
SHA-256: 00243ff88a1ec8f32de98f0f7b6a575d43161e77a09957b96a4b95f9a1bc9e5e