Malicious PDF — malware analysis report

Static analysis result for SHA-256 aadf731469b2c838…

MALICIOUS

PDF

74.3 KB Created: 2021-07-15 17:03:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: a1908869f054613fbf215cd696fcb8b9 SHA-1: 1398874c05e20631bdc5b8d73795a9d0c914f0de SHA-256: aadf731469b2c838b7cc3ed7482d9ce8f4426eb43ed5319f604f4290e154b603
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated maliciousness. A high-severity heuristic identified an image lure linking to an SEO redirector, which points to a phishing attempt. While no scripts were directly extracted, the PDF structure and the presence of external URIs suggest it's designed to lead users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7056

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/HbdJGeoIq_s/square?utm_term=string+to+array+string+c%23 PDF link annotation
    • https://static1.squarespace.com/static/60aac4e0d5abe22cec5c4b22/t/60f00b1ee4fb0f110d7c030a/1626344222496/75771674374.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf69b23f3791685666e32d/t/60ee1eae9c71001bedf38712/1626218159120/minerals_are_micronutrients_required_by_the_body.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60ee10a5537273346e2c14f8/1626214565615/32644998960.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4e0d5abe22cec5c4b22/t/60ec93c1cd1a1204f6c98218/1626117057285/the_cat_who_walks_through_walls.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_off0000be89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE89 17732 bytes
SHA-256: 3dc8cd45873d694ac75529c14acff0942c811572bc68e7c150e64d7d032aa86c
font_01_sfnt_off0000ed9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000105b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B5 10416 bytes
SHA-256: 64723df6b0e739a7256e5785b4b87c4f6e5bbdccd3cdae387c3c98050eaa9968