Malicious PDF — malware analysis report

Static analysis result for SHA-256 b39cc612602d615b…

MALICIOUS

PDF

77.0 KB Created: 2021-07-12 22:19:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 574005b34ec3e8f1cc8eae56bb0c17a9 SHA-1: 3b779e437bb1eeced2450fc49b6dd5ccf1fb12ee SHA-256: b39cc612602d615b602e1b8a75dcdc336ea9b03b8aceb4b2e4d3c2bea981688f
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. A high-severity heuristic identified an image lure linking to an SEO redirector at 'https://wastran.ru/square?utm_term=tweaked+lower+back+while+squatting', suggesting a phishing attempt. While no scripts were explicitly extracted, the PDF structure and the presence of external links point towards a malicious document designed to lure users to a potentially harmful site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7604

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://wastran.ru/square?utm_term=tweaked+lower+back+while+squatting PDF link annotation
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60e93dd7320dbd0de281faa6/1625898455381/check_my_laptop_battery_health.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60ec7a2e72e2584f24624c2d/1626110510661/85248496894.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60e7922b687a3d659a47d4a5/1625788971986/red_mini_poodle_price.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_off0000ccbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCBC 11176 bytes
SHA-256: 687c7ae34db4034537b98ad898f972d5ce6a2ba4eab7dc5b3e94f501e7f97e43
font_01_sfnt_off0000e65c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE65C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE6E 16228 bytes
SHA-256: 47d322288de5bfa6d24af9f7aaff36fd263b79a130591c7ceff9f1f0320db845