Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f7ce4443f39b80…

MALICIOUS

PDF

44.6 KB Created: 2020-09-06 02:28:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: db3732dbdf90ddc26374534670633d29 SHA-1: 20277ed037a91009de7f22a320e06cb602aa02d1 SHA-256: 28f7ce4443f39b8071c201ded020d59f0306e43374fe47213bf9d4880821739c
152 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.me, which is likely intended to lead the user to a malicious site. The document body, though heavily obfuscated, contains the same URL and references a 'candidate strengths and weaknesses form', suggesting a social engineering lure. The presence of numerous other links to static.usrfiles.com, while marked as benign, indicates a link farm strategy. 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.me/wix?keyword=candidate+strengths+and+weaknesses+form
    • https://static.usrfiles.com/ugd/76dd3d_6df1af7f849c4413a3adb57a0b54d15b.pdf
    • https://static.usrfiles.com/ugd/cafc24_9ba86247281a4a49947e5be93eb97ab4.pdf
    • https://static.usrfiles.com/ugd/39cb9d_95ae60e3a7454a06aec7517fe153b314.pdf
    • https://static.usrfiles.com/ugd/b8c837_e3fc20c6cc5443b78b1646e33f733bc0.pdf
    • https://static.usrfiles.com/ugd/b926a8_74cbac2e29f9407cb7a5f39327b449a2.pdf
    • https://static.usrfiles.com/ugd/ad8f3a_6dda45f3bc9d45ce83aa0cb819af074a.pdf
    • https://static.usrfiles.com/ugd/902d29_dc788dff7f37474b8a1d5ed8b20b1a66.pdf
    • https://static.usrfiles.com/ugd/0511f5_e60ee88a0f754df6b718cc4f51b63c85.pdf
    • https://cdn.shopify.com/s/files/1/0428/9318/1095/files/chunky_black_boots_platform.pdf
    • https://cdn.shopify.com/s/files/1/0430/9037/8903/files/57456932313.pdf
    • https://static.usrfiles.com/ugd/03a576_8b9244290e58455690256ba832399032.pdf
    • https://static.usrfiles.com/ugd/91e123_a477c2b1e61c47aa89b2443952d524ac.pdf
    • https://static.usrfiles.com/ugd/9c43ec_1c66a8e575cf4cc08f047f5d8884c3de.pdf
    • https://static.usrfiles.com/ugd/b11f6d_76684124286a49e782dfca465191933b.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_off0000713c.bin
964bd27bf16b9515c108f0d86b2822afb050909401f01c41cc64ce7ca97a2966
pdf-font-stream PDF embedded font (sfnt) at offset 0x713C 5348 bytes
font_01_sfnt_off00008355.bin
c71931d8a2bff00abbe66dcd95cb3313e43ad9339bb6b71cb29bd9fe48933aef
pdf-font-stream PDF embedded font (sfnt) at offset 0x8355 10104 bytes