Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd9de30fe18a2d5f…

MALICIOUS

PDF

66.2 KB Created: 2021-04-23 06:30:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: b2a1109bc448525d7169ae5191a837d1 SHA-1: 58823bb42e1b8043c358d089c5b2b47730e39361 SHA-256: bd9de30fe18a2d5fb5eef6c84c7baff200f71acedbb599589de5ac250b800795
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or malware distribution. The document body, though heavily obfuscated, contains strings that appear to be related to the URLs, suggesting an attempt to disguise the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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://www.dgs-interparts.be/sites/default/files/42042694998.pdf In PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/zuguxinukebezukul.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/viwiredozilopuvotudulufez.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/newusagolepilukakatukus.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/35095474677.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/65827293628.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/mimixinaxeralowevowijut.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/dalobasowi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=tyt+th-9800+4m+modPDF link annotation
    • https://www.vub.be/sites/vub/files/webform/86005813007.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/muvebijamalixodimobowase.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c16b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC16B 5212 bytes
SHA-256: 5b63a2b50d1dcd6a64ae8f456527af88a88e303abb19072c8eadd177fc075f32
font_01_sfnt_off0000d31c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD31C 12888 bytes
SHA-256: e9b59caa29630d796f14cab2c9fbd789e4f116ef12d7dc79a3e5eb2ec2cda5eb