Malicious PDF — malware analysis report

Static analysis result for SHA-256 8db3ad1a4cc2d167…

MALICIOUS

PDF

78.2 KB Created: 2021-07-13 01:07:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 1d6e78e9c6f2af82fc1e137117b46471 SHA-1: 28c6840718304ab11c8fb0f79ee2d33792bb7181 SHA-256: 8db3ad1a4cc2d167e1cbb49fb911e72175942565507b61d0c951c940ab9b68f0
136 Risk Score

Malware Insights

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

The PDF contains a high-severity heuristic indicating an image lure linking to an SEO redirector, suggesting a phishing attempt. The ML classifier also flagged the PDF as malicious. While no scripts were extracted, the presence of an external URI and the ClamAV detection point towards a malicious document designed to trick users into visiting a potentially harmful site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6198

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
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://feedproxy.google.com/~r/sq/ugae/~3/rCno-htTzZk/square?utm_term=html+manual+of+style PDF link annotation
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60e782b555092d783c617024/1625785013891/zarefevimijuxoxin.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e8e54e0cbdad4d350311fa/1625875790082/infusible_ink_on_cotton.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60e792ee7be683581cdebefa/1625789166802/hardin_county_probation_and_parole.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_off0000d1c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C0 16864 bytes
SHA-256: 4510bcfea31d6d409d91951fc88a375dd47cab1692a2607be009597dae1473d7
font_01_sfnt_off0000fdde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F5 10388 bytes
SHA-256: 398d1722585d9a2b953c9d04029e38e15dae47aeef1d2dc9a6c92f918311f2d9