Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf2439ccffa4a30f…

MALICIOUS

PDF

44.2 KB Created: 2020-09-01 00:18:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f153770c11d9a44d1f1f9c63b460e80a SHA-1: a6bb829dcb5e308464c0b8df2c426dbcc1a673aa SHA-256: cf2439ccffa4a30ff9da317d329308767048c0b3f92fc2e9951c8285eb00d657
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, which is also present in the document body. The link leads to 'ttraff.ru', a known malicious redirector. The document also contains a large number of embedded links to 'static.usrfiles.com', suggesting a link farm or SEO poisoning tactic. The ML classifier strongly indicated maliciousness.

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/pify?keyword=kakamega+county+jobs+for+form+four+leavers
    • https://static.usrfiles.com/ugd/cc03df_e385d98300724a69928bdbfc640bafe6.pdf
    • https://static.usrfiles.com/ugd/d7ba0f_adb28e9d16534f1f9716e48c22fc48b1.pdf
    • https://static.usrfiles.com/ugd/b8c837_eeeec7059f2c46c69f5ad0e5a6696a2e.pdf
    • https://static.usrfiles.com/ugd/d9d1f5_3e2f6ab32bfb4157b61490db3b1e4260.pdf
    • https://static.usrfiles.com/ugd/345929_6f934eae1fdc49e3ad8bb77bcdd32aa1.pdf
    • https://static.usrfiles.com/ugd/ca300b_12a8c0644c7f4e2eb977fa2ed954d422.pdf
    • https://static.usrfiles.com/ugd/b8c837_1ac3c43eabc7466497d2b29eb1063d4c.pdf
    • https://static.usrfiles.com/ugd/739437_f15dd49ef0204de993eb8fe12f484d35.pdf
    • https://static.usrfiles.com/ugd/9e53d4_80af588d27c64697bb6a72632a71bc58.pdf
    • https://static.usrfiles.com/ugd/de3d83_c61265f90e0249389d981f8072dd0fd4.pdf
    • https://static.usrfiles.com/ugd/b8c837_6d956ce77f8b44fa80c665f0e1b82399.pdf
    • https://static.usrfiles.com/ugd/38eac1_067bdfddd49a4e82b476ddf6a3b57303.pdf
    • https://static.usrfiles.com/ugd/1813b3_3b228ca0bd6243bfa7ad3ab8d4677c33.pdf
    • https://static.usrfiles.com/ugd/6c032c_fd81cd62aae347368501d807fcae057b.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000589d.bin
0ecab52a1149f17b73828237f9d92038a9b8e4965d8da478772f820c325f7a56
pdf-font-stream PDF embedded font (sfnt) at offset 0x589D 5612 bytes
font_01_sfnt_off00006bbc.bin
470cf721c52a64197eb003b1124155af7fed0d54c76e925eeedfa0dd10ffd3ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x6BBC 10120 bytes
font_02_sfnt_off00008e6b.bin
b0e6e7b413e90826d6de5c462ffb73d27c17a48f997ba472566106b0f7d3ba34
pdf-font-stream PDF embedded font (sfnt) at offset 0x8E6B 16216 bytes