Malicious PDF — malware analysis report

Static analysis result for SHA-256 b818c51f77b486fd…

MALICIOUS

PDF

79.4 KB Created: 2021-07-14 04:37:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 4f9a0a4b28858f895a895d98a5f18fba SHA-1: 31e2719655a6798df86e59f12287699da5f1f450 SHA-256: b818c51f77b486fdfdd9c15fe9e6cb85322cac6fcc95271bbf04a14aa241fcc4
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains heuristics indicating it is a phishing lure, specifically using an image to redirect users to a URL. The ML classifier also flagged it as malicious. While no scripts were extracted, the PDF structure and embedded URLs suggest a phishing attempt to trick users into downloading further malicious content or visiting a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6166

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/razvivatel/yapz/~3/IdU8rIDf9lQ/square?utm_term=calling+your+bluff PDF link annotation
    • https://static1.squarespace.com/static/60bf6c89a2b0b938881bcf91/t/60edfa9a24c32e4364b75aee/1626208922718/final_cut_pro_lower_thirds_templates_free.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf69b23f3791685666e32d/t/60ecb37c74517d3de2179b92/1626125180333/9903470851.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6c89a2b0b938881bcf91/t/60e94d47e6bd1231e6094a6c/1625902407730/on_superstition_by_ag_gardiner.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6cad3a95e91b59aa2418/t/60e8f40fe6a58043b68f8baa/1625879567696/57387139335.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_off0000cf28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF28 20344 bytes
SHA-256: a8e70c0a65122c3d35338601c1fad0b98f605c51a65e685b6510f1f8834f0452
font_01_sfnt_off00010270.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10270 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A87 10376 bytes
SHA-256: ea2987ecd321f39da1cf3ac8ae448c8e00ac7c64ca48765baf5795f056b72db0