Malicious PDF — malware analysis report

Static analysis result for SHA-256 83075aa212c1214b…

MALICIOUS

PDF

75.0 KB Created: 2021-07-13 22:08:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: fb6b3be059f04822624a9d0b4cce7fa3 SHA-1: 94fffd7c2f76d74b14a9253d2af2c3a40098c836 SHA-256: 83075aa212c1214b8ac42660f0d862a41ed4aa488b44b01adf69981ff69ae08f
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a high-severity heuristic firing for an image lure linking to an SEO redirector, identified as a free-download phishing attempt. The external URI points to a suspicious domain, 'nomylo.ru', which is likely the phishing landing page. While no scripts were explicitly extracted, the PDF structure and the nature of the redirector suggest a phishing attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7788

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://nomylo.ru/square?utm_term=nationalization+of+resources PDF link annotation
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e7b7a3afd06e4982e8b3e8/1625798563470/77144066801.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4e0d5abe22cec5c4b22/t/60e7ae69dbb92d34f5ac58de/1625796201379/the_great_hunt_wendy_higgins.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e8b581b2c1ff66526ff081/1625863553247/78797123261.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_off0000c5f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE05 16212 bytes
SHA-256: edf8e600d37fbe4f3d9584c5cd31832c84c3936b4a9b419d32b712ca5fa3a433
font_02_sfnt_off0001082e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1082E 10468 bytes
SHA-256: 877caf07c04d6659976c1344a8d41ef00651b543c42187d120540abc0390bfe9