Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bf9281099d0e5f3…

MALICIOUS

PDF

41.4 KB Created: 2020-09-01 01:10:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0531ea6a3ada49d286f58f5b975ac8d8 SHA-1: 8332040805fe7566e2cb65588c6155b8a6f5798e SHA-256: 7bf9281099d0e5f38096f756b822a1d399dca71090c2863e19408f46acf78982
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector infrastructure, disguised within content that appears to be educational worksheets. The ML classifier strongly indicates maliciousness. The primary IOC is the redirector URL, which is likely used to host or distribute further malicious content.

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=conjunction+worksheets+for+grade+7
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/6417/2445/files/xefavonotegazapag.pdf
    • https://cdn.shopify.com/s/files/1/0431/5290/0250/files/rbi_guidelines_foreign_currency_convertible_bonds.pdf
    • https://cdn.shopify.com/s/files/1/0431/3822/0181/files/babysitting_cream_game.pdf
    • https://static.usrfiles.com/ugd/30e015_327d0eb9cb854fc196e2083df1c5de98.pdf
    • https://static.usrfiles.com/ugd/724fb5_e61f515ee4af434e809b15e4765faa31.pdf
    • https://static.usrfiles.com/ugd/b8c837_c3f3980ecb40432683dddd56453d5a04.pdf
    • https://static.usrfiles.com/ugd/c3548c_c79ff1c2fa8a406bac3c871cddd4cdda.pdf
    • https://static.usrfiles.com/ugd/c3548c_91ad70d93c77499bb5301259975ae9c0.pdf
    • https://cdn.shopify.com/s/files/1/0438/2579/1138/files/ziduwaxipiwumelir.pdf
    • https://cdn.shopify.com/s/files/1/0434/4535/4658/files/algorithmics_the_spirit_of_computing_harel.pdf
    • https://cdn.shopify.com/s/files/1/0431/7741/0720/files/zagokuxu.pdf
    • https://cdn.shopify.com/s/files/1/0432/0867/1394/files/bipotesigolit.pdf
    • https://static.usrfiles.com/ugd/0aab01_5bd1c3e83ebd45fdb1288fbb856816e4.pdf
    • https://static.usrfiles.com/ugd/19103d_a3b29374dc6c4f20a849be6a330e5004.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_off0000620c.bin
0c5fb38ee9cb070ea06f80043f5091022afffca81e6550a78dd6ccf4f44997f4
pdf-font-stream PDF embedded font (sfnt) at offset 0x620C 5468 bytes
font_01_sfnt_off000074be.bin
35a78ef8137ef0b6d8c64859005e01f5a1f53fc9832f7657cd821efe98b7f5b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x74BE 10564 bytes