Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6545f2f0988985a…

MALICIOUS

PDF

75.4 KB Created: 2021-07-12 20:48:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 3ddba5dbb35d1ed246df5147b67ab04d SHA-1: 65ecd6ebb28170411272e9ac9303395505f76853 SHA-256: b6545f2f0988985abe9a07207f6c1a51e4b32ce72f21cc967bda02aa73381173
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and ML classifiers indicated maliciousness. Heuristics identified an external URI and an SEO redirector link, suggesting a phishing lure. Although no scripts were extracted, the presence of these indicators points to a phishing attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7703

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/WVKuihPcy9U/square?utm_term=saw+in+afrikaans PDF link annotation
    • https://static1.squarespace.com/static/60bf6cad3a95e91b59aa2418/t/60e77115cba01e017d443228/1625780501095/66573877835.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60ec701412c1416d2f18b37a/1626107924711/principles_of_biology_lab_manual_5th_edition_answers.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6cad3a95e91b59aa2418/t/60e84a7248bd770cc468bad8/1625836147090/kugunaxotigojuwipifafe.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_off0000c838.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC838 16900 bytes
SHA-256: fa7e66fb4f01f41f2b5dd0b24baa27318a1594de04e2eecd019faf4372e612d4
font_01_sfnt_off0000f3c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010bdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BDD 10064 bytes
SHA-256: 9bde71e56654bd903493259be681f6a3112d086e300c6fc3b5bd59bfea7c0b74