Malicious PDF — malware analysis report

Static analysis result for SHA-256 a21310ad7242eaa2…

MALICIOUS

PDF

44.6 KB Created: 2020-09-06 13:04:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f8d929c785bd5bbec11a4661e16ddd74 SHA-1: 501abe0b765aedcf6f2100bc8bb2f37dc64be57b SHA-256: a21310ad7242eaa2630790ae3d39f89e1a8422f4e4b658f1153bf714539fc0cb
152 Risk Score

Malware Insights

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

The PDF contains embedded links, one of which, https://ttraff.me/wix?keyword=caged+chords+pdf, is identified as a malicious redirector. The document body, though heavily obfuscated, also contains this URL, suggesting it is the primary lure. The presence of a large number of external PDF links, many pointing to static.usrfiles.com, indicates a link farm strategy, likely to improve search engine ranking or distribute malicious content. No scripts were extracted, limiting the analysis of direct execution capabilities.

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=caged+chords+pdf
    • https://static.usrfiles.com/ugd/b8c837_a2298079133140999817f0eb7840f75a.pdf
    • https://static.usrfiles.com/ugd/c2007e_30ac26114c33419389648d0037e659a8.pdf
    • https://static.usrfiles.com/ugd/b8c837_3872781a27ec40df8fe96473d4beda52.pdf
    • https://static.usrfiles.com/ugd/8c0e65_b3022e99260b4c8baa43cd7158bab6ec.pdf
    • https://cdn.shopify.com/s/files/1/0430/5354/7677/files/topotobujulimexum.pdf
    • https://static.usrfiles.com/ugd/c83fdb_eb23b17d5e864ac3b62443f3a7bcf842.pdf
    • https://static.usrfiles.com/ugd/0511f5_7da76cfeedec4eb6ac3318cc0bc6aaf6.pdf
    • https://static.usrfiles.com/ugd/b88e3d_3fd8ced6d10c4010b5aa2fd11b021743.pdf
    • https://static.usrfiles.com/ugd/7a13df_22439aba1d734694b858efedd9858603.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005c3b.bin
c2c32f7e9072bf1c5bc8d5527347a539224c63d50de7927dc8b0bf526368436f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C3B 5292 bytes
font_01_sfnt_off00006e35.bin
ccc28b57f7d7b9d3aac745b7a51bb95aa351c7e286ee3aaf35fdddc0cb886655
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E35 10072 bytes
font_02_sfnt_off000090eb.bin
15a68420f1c377824b8c1fd571ac7c30556db1b4bc05006bf44ec3f6c6c83208
pdf-font-stream PDF embedded font (sfnt) at offset 0x90EB 16120 bytes