Malicious PDF — malware analysis report

Static analysis result for SHA-256 a32de2071dc61505…

MALICIOUS

PDF

54.2 KB Created: 2020-08-31 19:49:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 231aef4d1940f761e81adc28a0d79be4 SHA-1: 04cd455e4221b9a333d6bf184836c0953f0720bb SHA-256: a32de2071dc615052e8ae0897ddc3b11dfd61574d7491f15b303cb0cc14334dc
154 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the text 'Finding common denominators fractions worksheet' and the malicious URL 'https://ttraff.ru/wix?keyword=finding+common+denominators+fractions+worksheet'. This suggests a lure to a malicious site, potentially for phishing or to download further payloads. 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.ru/wix?keyword=finding+common+denominators+fractions+worksheet
    • https://static.usrfiles.com/ugd/bb13a2_aa8aa9dfba53435a8e852d56ff577cea.pdf
    • https://static.usrfiles.com/ugd/07ef24_a3319a050f0843ea9f4e413a8186ad6e.pdf
    • https://static.usrfiles.com/ugd/2ac701_30486ecfa5cd416982312f97d7325260.pdf
    • https://static.usrfiles.com/ugd/173616_c6f8c46b292b40fc876e6826b68a2de4.pdf
    • https://cdn.shopify.com/s/files/1/0433/9692/3543/files/92264038567.pdf
    • https://cdn.shopify.com/s/files/1/0431/4041/5644/files/tusoremudobudopifu.pdf
    • https://cdn.shopify.com/s/files/1/0433/7529/6677/files/87541150426.pdf
    • https://cdn.shopify.com/s/files/1/0431/6427/0743/files/lawumuvaguxijuvagedetag.pdf
    • https://cdn.shopify.com/s/files/1/0438/6222/9142/files/96936481852.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/28650507632.pdf
    • https://static.usrfiles.com/ugd/5899d5_ce55ba71e56346e4b8479056bea628c9.pdf
    • https://static.usrfiles.com/ugd/b48b60_05f26f18a84a4eb2bac06e20fcccf64f.pdf
    • https://static.usrfiles.com/ugd/b8c837_e62dca9eb4164cc580e4e8856dd25dcd.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_off000082f5.bin
6c10b608c37b00157db7e1e610afd58226fe877d4c393e6b75423b1494676f38
pdf-font-stream PDF embedded font (sfnt) at offset 0x82F5 5512 bytes
font_01_sfnt_off0000959c.bin
a7ea785ce675d3128fbb550c22d7ce0878eee4f5bd8a6970f0377107ef85616d
pdf-font-stream PDF embedded font (sfnt) at offset 0x959C 9580 bytes
font_02_sfnt_off0000b696.bin
de5e424296fca6632de503ebef56d41c9898c13bba2aba3354ff7f3c3578a82d
pdf-font-stream PDF embedded font (sfnt) at offset 0xB696 16116 bytes