Malicious PDF — malware analysis report

Static analysis result for SHA-256 d84f6d03f4fc9d8a…

MALICIOUS

PDF

74.8 KB Created: 2020-08-29 03:54:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eb2b7e65aac2d8db278f0da94d32304d SHA-1: 7d4ef9d3cfc76c544ce6dfbb7cb4b99373bc143c SHA-256: d84f6d03f4fc9d8a6cf6cfcc3faf9da5f7051b08d985ef1e897bd5a2841b55c8
154 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating a link to a known malicious redirector. The document body, though heavily obfuscated, contains the URL https://ttraff.ru/wix?keyword=area+where+b+cells+become+immunocomp, which is also listed as a malicious redirector. The presence of numerous other links to static.usrfiles.com suggests a link farm or content delivery network used to host malicious files.

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=area+where+b+cells+become+immunocomp
    • https://static.usrfiles.com/ugd/b8c837_a4d71394db514285b0e877aaeb746780.pdf
    • https://static.usrfiles.com/ugd/b8c837_98fe4ef2b21646f48007bab19c207499.pdf
    • https://static.usrfiles.com/ugd/b8c837_725639628d584dd48b143e5adc3fa149.pdf
    • https://static.usrfiles.com/ugd/b8c837_db80b0e0394b451c86e1fafbd4b6ea36.pdf
    • https://static.usrfiles.com/ugd/b8c837_5ac3ee028dd74febb13802a87a7de7f6.pdf
    • https://cdn.shopify.com/s/files/1/0437/0461/5066/files/94499512678.pdf
    • https://cdn.shopify.com/s/files/1/0462/3607/4133/files/91448660700.pdf
    • https://static.usrfiles.com/ugd/b8c837_ffb888ccdff74888b90bfa85a1dd202f.pdf
    • https://static.usrfiles.com/ugd/b8c837_538721c2a6c542a3807f4fcdeba1b002.pdf
    • https://static.usrfiles.com/ugd/b8c837_8657dfc8d9494d70855fa76bb9c1a0e7.pdf
    • https://static.usrfiles.com/ugd/b8c837_baa277f25a374441b94f96ba31ad475b.pdf
    • https://static.usrfiles.com/ugd/b8c837_da0e981594ba4776892747714e25d664.pdf
    • https://static.usrfiles.com/ugd/b8c837_d08cb33ae5f14941bfc7375b4b153197.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_off0000e5b8.bin
9e92420f93f3a602d0d577f9778fcd4319d632edf3bf23b541cdfc0421fc6ae9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B8 5396 bytes
font_01_sfnt_off0000f7f4.bin
f1693a99d3963e81aee51e22cff3bf78d55bafcf8e10e9aece451e543188144f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F4 12188 bytes