Malicious PDF — malware analysis report

Static analysis result for SHA-256 52cf113d1502e77d…

MALICIOUS

PDF

45.7 KB Created: 2020-08-30 06:45:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 17eb14f8c6c56fc74950d7aa2c2f155a SHA-1: 37d44b6b71ed436fa2ff5d989618287ba5cf4729 SHA-256: 52cf113d1502e77d89823e8c5554cf1a414f831c4259f431b4c9d2ee63852284
152 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link, specifically pointing to 'https://ttraff.com/wix?keyword=how+to+use+quip+toothbrush'. The document body, though heavily obfuscated, also contains this URL and appears to be a lure related to 'how to use quip toothbrush'. The PDF also exhibits characteristics of a link farm, with numerous embedded URLs, many pointing to static.usrfiles.com. The ML classifier strongly flagged this PDF as malicious.

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=how+to+use+quip+toothbrush
    • https://static.usrfiles.com/ugd/b8c837_5d9ce65985f04624af29ce8956bcafa9.pdf
    • https://static.usrfiles.com/ugd/0ebc1f_8dba8678c69a46e38f65c5e5ae2abd71.pdf
    • https://static.usrfiles.com/ugd/b8c837_375c03069b3d4bc0bc11542149eb8ceb.pdf
    • https://static.usrfiles.com/ugd/15cd4d_6ec0df0f820147838217b933ffc17ec5.pdf
    • https://cdn.shopify.com/s/files/1/0433/9410/5509/files/85870590711.pdf
    • https://cdn.shopify.com/s/files/1/0433/4272/5275/files/computerized_accounting_system.pdf
    • https://cdn.shopify.com/s/files/1/0438/2218/6656/files/brokerage_house_report_on_tata_motors.pdf
    • https://cdn.shopify.com/s/files/1/0430/4017/8333/files/83268176463.pdf
    • https://static.usrfiles.com/ugd/3826db_3a01256899424b6c8bd856a77cf6afb4.pdf
    • https://static.usrfiles.com/ugd/0d9a50_6b17a296cec64b94bcee19ac02c8a622.pdf
    • https://static.usrfiles.com/ugd/b8c837_ef21abd4d10d4d0490ede476d398db3f.pdf
    • https://static.usrfiles.com/ugd/b8c837_8901d2675ded4b4db21fc507091c7d55.pdf
    • https://static.usrfiles.com/ugd/7f929b_7ddb968e9c8647e4bb1859719cd31110.pdf
    • https://static.usrfiles.com/ugd/e4ff69_3065c49d78514589a54d04a802c7c8f2.pdf
    • https://static.usrfiles.com/ugd/a1fb72_0a19f3856a1142a38ab382124a3e5d9c.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_off00007500.bin
3fb900d3f83bc8c4a4bf1a17f7e7b0426ce75c89ad4a8154e7fa955593c182e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x7500 4984 bytes
font_01_sfnt_off000085ff.bin
0d3c0637c47172dbdc8facd06b271e1240c9e8fe7fd272f9e9cb7056f171c55f
pdf-font-stream PDF embedded font (sfnt) at offset 0x85FF 10448 bytes