Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8a435c376013d0c…

MALICIOUS

PDF

73.1 KB Created: 2021-07-12 20:37:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 4bed6c3297a6deae5ca179bcfd5bb2df SHA-1: b74ffe41f73382211ddb88aa4399e88f9b287991 SHA-256: d8a435c376013d0c820eb076eacc60d85e27e5f56943dd61fc1d52a49a18217d
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded URI that functions as an SEO redirector, identified as a lure for free downloads and phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and heuristic firings suggest it's designed to lead the user to a malicious site, likely for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7185

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/razvivatel/yapz/~3/XMoLd4EPXkg/square?utm_term=formality+in+tagalog PDF link annotation
    • https://static1.squarespace.com/static/60bf6cad3a95e91b59aa2418/t/60ec78affd54eb070824abf0/1626110127975/the_croods_new_age_full_movie_free.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60ec7b3d668ba31612b53826/1626110781922/orthostatic_hypotension_underlying_causes.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60e8e8b62a6f785f58317454/1625876662193/gunajeruduba.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_off0000be38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE38 10240 bytes
SHA-256: a71100bd13b6cbe694b290db3810ef3f085c809e934a0d35394e3ef1d5da7a72
font_01_sfnt_off0000d52a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD52A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ed3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3C 16920 bytes
SHA-256: 8c0133d40481a9eb55777076a619d419309e0cd447d069bd074f1b4f98851ff5