Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd74f3a1f504e7e7…

MALICIOUS

PDF

42.2 KB Created: 2020-08-31 06:25:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2dacfae07abedf55a877723894270ac2 SHA-1: 4ee35bdc835f3c9b82b69f4eb11137850030fd43 SHA-256: fd74f3a1f504e7e7a96d42d91cd8bca2554c5aadec4c3c48ddf77472d2694011
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains embedded links, one of which points to a known malicious redirector. The document body, though heavily obfuscated, contains text that appears to be a service manual title, suggesting a lure. The presence of a large number of external PDF links, many pointing to static.usrfiles.com, indicates a link farm strategy. The ML classifier also strongly flagged this PDF as malicious.

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.ru/wix?keyword=bernina+virtuosa+150+service+manual
    • https://static.usrfiles.com/ugd/0779a3_2627dfdaeb224e1bbab6c77e5a445f31.pdf
    • https://static.usrfiles.com/ugd/33ab24_bace3dd589964fde96ecd4c293232705.pdf
    • https://static.usrfiles.com/ugd/b6edda_2015db672acf47589a13a73ffc081bea.pdf
    • https://static.usrfiles.com/ugd/cbdbb6_be6fea4ba1e34fbda3ffaeb224b9abd5.pdf
    • https://static.usrfiles.com/ugd/eb4c03_f8c9645cf4664ad5bd0c314b30288a33.pdf
    • https://static.usrfiles.com/ugd/cb2bed_ddcb62815b904a0ca9f9b68499c7d734.pdf
    • https://static.usrfiles.com/ugd/b8c837_2c354ab937614221a690f8e5650ebb8a.pdf
    • https://static.usrfiles.com/ugd/b8c837_bf40f4c26e664fb09c7741a6be1858b6.pdf
    • https://static.usrfiles.com/ugd/ae059d_7f4ff1a879cd4ca79d826008b6a2dd53.pdf
    • https://static.usrfiles.com/ugd/b8c837_c18c34ad10884e728dd5f90b0d3ff43b.pdf
    • https://static.usrfiles.com/ugd/b8c837_503930efaa134338ab701eb24487daf0.pdf
    • https://cdn.shopify.com/s/files/1/0440/0644/1125/files/prime_video_australia.pdf
    • https://cdn.shopify.com/s/files/1/0434/9906/1408/files/active_and_passive_verbs_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0430/3064/2837/files/pebazomujedu.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_off00006643.bin
c7399425c151276ea25514686dd24b3f05ec1a0f7d5f258e74c1e42b5ca7ed26
pdf-font-stream PDF embedded font (sfnt) at offset 0x6643 5372 bytes
font_01_sfnt_off0000787a.bin
1b0821ded92b260ec5b1a05071ed2219ae18a20042639e88a46ca5533be80f2a
pdf-font-stream PDF embedded font (sfnt) at offset 0x787A 10680 bytes