Malicious PDF — malware analysis report

Static analysis result for SHA-256 9400b656bf720a5b…

MALICIOUS

PDF

68.8 KB Created: 2021-04-14 01:24:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 02390cace15338060b22f06e4d96d3c7 SHA-1: 206ca854a8edd1f9988b497bccec36f0235e3e14 SHA-256: 9400b656bf720a5baa296574fe6e7bb3a1195458a1e2a667a24a67dc24b3dfe6
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm with numerous external URIs, many pointing to unknown or potentially malicious domains. The presence of embedded URLs and the nature of the heuristics suggest this document is designed to redirect users to attacker-controlled infrastructure, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://architecturaldesigninc.com/sites/default/files/36110977311.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/memirudomonejusowanasu.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/jizexatunurometubukos.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/gewematumupam.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/61943826361.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/6948618973.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/98751459569.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/mikax.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/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=r+controlled+vowels+lesson+plans+2ndPDF link annotation
    • https://gradfutures.princeton.edu/system/files/webform/48950823745.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/muvebijamalixodimobowase.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/midari.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_off0000d258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD258 5360 bytes
SHA-256: 5f1adbe16467708727c5dcc9d5fa3665dc4bb02430ba1196c8e14e801f07dbc0
font_01_sfnt_off0000e4b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B6 9960 bytes
SHA-256: b3154974d1f4c94d9d64b0ad588eab276b30882f5d3d8ec25a58c6407af4e91f