Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ef7b85144960e19…

MALICIOUS

PDF

46.5 KB Created: 2020-08-31 20:20:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 36c41dbe1ba9b35446132cc5e9a1d8be SHA-1: 27a7021e70a2677d7bbc44ed9da560cefe12e568 SHA-256: 8ef7b85144960e19a03d4071b43c7fbfcdb04c22ff3e1a0da5431793d749e3d5
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged as malicious by a machine learning classifier and contains a large number of embedded URLs. One of these URLs, https://ttraff.com/wix?keyword=budget+sheet+template+pdf, is identified as a known malicious redirector. The document body, though heavily obfuscated, also contains this URL, suggesting it is the primary lure. The presence of numerous links to external PDF files, many hosted on static.usrfiles.com, indicates a link farm designed to distribute malicious content or redirect users to phishing sites.

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=budget+sheet+template+pdf
    • https://static.usrfiles.com/ugd/b8c837_6a60fd1361b84521a6891fcd4932acbd.pdf
    • https://static.usrfiles.com/ugd/f46427_44481c50ac52422eb6c41b0ecabf1bd2.pdf
    • https://static.usrfiles.com/ugd/a2d007_6d808d64c12e40cb87ffe85dff170b4a.pdf
    • https://static.usrfiles.com/ugd/b8c837_808c6002d3e9422e858b5d6bff11192b.pdf
    • https://static.usrfiles.com/ugd/db93e9_09a646286a114f468ced3822795edac7.pdf
    • https://cdn.shopify.com/s/files/1/0431/2173/7882/files/nfz_krakw_batorego_informacja.pdf
    • https://cdn.shopify.com/s/files/1/0437/9115/5361/files/rudazalixezukifeta.pdf
    • https://cdn.shopify.com/s/files/1/0434/1858/3192/files/dopiwa.pdf
    • https://static.usrfiles.com/ugd/868401_8131c99656554f07b82f184962e7aac7.pdf
    • https://static.usrfiles.com/ugd/b6edda_8baf56c360804a4ba9a3c75b1b52a840.pdf
    • https://cdn.shopify.com/s/files/1/0433/7631/2471/files/20709923911.pdf
    • https://cdn.shopify.com/s/files/1/0465/3747/4198/files/wofuvuvotaxi.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_off00007652.bin
5290b720c2aebf9ca28b139751fd366216e7d8578b03bcd0175f1ef9c878e903
pdf-font-stream PDF embedded font (sfnt) at offset 0x7652 5408 bytes
font_01_sfnt_off0000889c.bin
ae3d3a4bbd8cabe930dbeff205296000e2db12caebeffcd2024acd990a67b0c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x889C 10956 bytes