Malicious PDF — malware analysis report

Static analysis result for SHA-256 d53967a6f3e6bb17…

MALICIOUS

PDF

41.0 KB Created: 2020-09-11 09:39:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 289584b8a7ee189397cc1f2a0ae73bd8 SHA-1: 1b3ac81b0737b2bf9b74433e2e66cea56e98b4e2 SHA-256: d53967a6f3e6bb17db1e0bc303d37f1182b1fdc7d699bf6a0e84dcac706eb61f
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF file contains a significant number of embedded links, with several pointing to known malicious redirector infrastructure. The ML classifier also strongly indicated maliciousness. The presence of a link farm heuristic suggests a large-scale distribution effort. No scripts were extracted, but the primary attack vector appears to be the redirection of users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://ttraff.me/wix?keyword=hourly+weather+report+chicago
    • http://files.drvsmusicclasses.com/uploads/1/3/0/8/130874085/04f901f140ba.pdf
    • http://files.apimagesart.com/uploads/1/3/1/8/131856318/3370b2314b.pdf
    • http://fojuve.galactosemiaresource.com/uploads/1/3/0/8/130874493/kuwuga.pdf
    • http://files.glenridgetkd.com/uploads/1/3/0/9/130969987/mezenazure.pdf
    • http://gipemezi.wcsuticklab.com/uploads/1/3/1/0/131070450/gazuzavonanogip-putisowanowu-jatobawaji-jerukoz.pdf
    • https://static.usrfiles.com/ugd/27135d_abe2c7b67da74df3a72b557becdcd235.pdf
    • https://static.usrfiles.com/ugd/b54ff4_503fbe0fbf604a909d856ee2d3e4f8ae.pdf
    • https://static.usrfiles.com/ugd/bc84a3_33de160b95954670a5252f0495ff5c4f.pdf
    • https://cdn.shopify.com/s/files/1/0432/2836/4968/files/maplestory_link_skills_guide_2019.pdf
    • https://cdn.shopify.com/s/files/1/0428/8787/2671/files/firebase_check_if_child_exists.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/sejil.pdf
    • https://cdn.shopify.com/s/files/1/0434/0200/2597/files/2565879708.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005475.bin
25905b5fbfc1d253871026dbd643d3b4826267050a1c415145393ff508044324
pdf-font-stream PDF embedded font (sfnt) at offset 0x5475 5172 bytes
font_01_sfnt_off00006621.bin
05df24f6b2c876052d66a58d6859d8c2ea6e854409235883ddaa6052cce78654
pdf-font-stream PDF embedded font (sfnt) at offset 0x6621 15340 bytes