Malicious PDF — malware analysis report

Static analysis result for SHA-256 77dc773e1fcb652b…

MALICIOUS

PDF

40.7 KB Created: 2020-08-30 21:26:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dd858fe659fb93e44ccdc0e69159fe9b SHA-1: e684da8912971b1b1676145be418cfa12932a8b6 SHA-256: 77dc773e1fcb652b9e30f37bdbd3038a3b32aab694ebae020eadba5d2412f999
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to a link farm designed to obscure malicious redirectors. One critical heuristic identified a link to a known malicious redirector at https://ttraff.com/wix?keyword=1997+cbr+600+f3+owners+manual. The document body, though heavily obfuscated, also contains this URL and other PDF links, suggesting an attempt to disguise malicious activity within a large collection of links. The ML classifier also strongly indicated maliciousness.

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.com/wix?keyword=1997+cbr+600+f3+owners+manual
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_c20b638aa6674bffbd0ea5704d0f8d8f.pdf
    • https://static.usrfiles.com/ugd/3aee12_19c6e9037f324635a610c160d998c65a.pdf
    • https://static.usrfiles.com/ugd/bd5c68_3dbae716a7de47e2a27cad53115c739e.pdf
    • https://cdn.shopify.com/s/files/1/0433/7011/9318/files/differential_pressure_transmitter_calibration_procedure.pdf
    • https://cdn.shopify.com/s/files/1/0435/4942/5823/files/xemizelemubozamesoxes.pdf
    • https://cdn.shopify.com/s/files/1/0437/2067/1400/files/monster_hunter_world_soundtrack.pdf
    • https://cdn.shopify.com/s/files/1/0435/1157/8776/files/320792227.pdf
    • https://cdn.shopify.com/s/files/1/0429/0091/4343/files/sinubakeriko.pdf
    • https://cdn.shopify.com/s/files/1/0428/2987/3318/files/tujanaduja.pdf
    • https://cdn.shopify.com/s/files/1/0429/8588/1759/files/bhakta_prahlada_movie_free_telugu.pdf
    • https://cdn.shopify.com/s/files/1/0435/9883/9970/files/jamadar_paper_final_answer_key.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000058ab.bin
e65e9e4b7026c99f644d657ee7693a0d16af4e6a2e176bd42468212c23c500a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x58AB 5912 bytes
font_01_sfnt_off00006cc0.bin
b9c7a76f525a981d406fc914dbb9162f82a35aac36720d7701c25cf4371b8e98
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CC0 13364 bytes