Malicious PDF — malware analysis report

Static analysis result for SHA-256 a552a2c6f4030c33…

MALICIOUS

PDF

112.1 KB Created: 2021-07-15 15:42:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 0fd39a9b0ef0ff6576ee6bf021487126 SHA-1: 9ca010fcbc3d066bf157f8934ab0dfd2405c58a2 SHA-256: a552a2c6f4030c33d2dda1fde2eb4f9dca8328a94a4d97e73ae80a6a5c70f206
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, with high-severity heuristics indicating it contains a redirector link. The embedded URL `https://crewmak.ru/square?utm_term=french+basque+country` is likely used to lure users to a phishing or malware distribution site. No scripts were extracted, but the PDF structure and heuristics suggest a phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6083

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://crewmak.ru/square?utm_term=french+basque+country PDF link annotation
    • https://static1.squarespace.com/static/60bf69b23f3791685666e32d/t/60e9322937da2614570ecb98/1625895465935/i_think_i_have_astigmatism.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60efced6161c06605435f8bf/1626328790803/17638463390.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60e8c16aaba27f4cd4bd0fd1/1625866602195/82366779768.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60ec8bf0950202184f1173d4/1626115056906/typescript_interface_array_of_objects.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_off0001526d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1526D 19480 bytes
SHA-256: ff64a00162a06be39555e74b37dba4fdedabaa2547865b1a1c88f3dcd06c2d69
font_01_sfnt_off00018458.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18458 10668 bytes
SHA-256: 6542d5de3c8639933049d7f9180d8a44c23d42ef8f7397f96164f27fa71ab6c7
font_02_sfnt_off00019cc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19CC3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1