Malicious PDF — malware analysis report

Static analysis result for SHA-256 05fcd2b95b233d81…

MALICIOUS

PDF

44.1 KB Created: 2020-09-01 00:01:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2c841ccfc41daf5676339505c1218de5 SHA-1: 7037482cd9a0aa97a6c606d3ffba080b70411e1d SHA-256: 05fcd2b95b233d814af5ff85bb881cf63482a68728fca5928cb10187ec399445
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, including one pointing to a known malicious redirector. The document body, though heavily obfuscated, appears to contain the same URL and references a 'worksheet pdf', suggesting a lure to trick users into clicking the malicious link. The ML classifier also 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.cc/pify?keyword=4+types+of+sentences+worksheet+pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_e5d6b7df37384fc9a880e88f05fb19f3.pdf
    • https://static.usrfiles.com/ugd/b8c837_fd6c8e0a3cb7448b9d2ccae6fdfe30c9.pdf
    • https://static.usrfiles.com/ugd/b8c837_033e081932ba49dc855b942949ec303f.pdf
    • https://static.usrfiles.com/ugd/3fc21f_44b0163bb4ca44b190d2811ee2ca1995.pdf
    • https://static.usrfiles.com/ugd/4cf28d_5621734c302543458a3b6a09e2424d94.pdf
    • https://static.usrfiles.com/ugd/ae059d_b4dd84cf1cf441f19eb6db97c31e514c.pdf
    • https://static.usrfiles.com/ugd/eed56f_05e4132b5c6f4146a2f2761f79d39423.pdf
    • https://static.usrfiles.com/ugd/b8c837_e29708be502f42099aadc15b0e736f8b.pdf
    • https://static.usrfiles.com/ugd/1be480_6f41766ceb304d54bc6b22104c9898ae.pdf
    • https://static.usrfiles.com/ugd/909b15_e3181eeb73b34b99b8a3d7ac0f12cb8a.pdf
    • https://static.usrfiles.com/ugd/80c1db_b0b655a6ba034041be0a7ed38748c8e3.pdf
    • https://static.usrfiles.com/ugd/4bdc6d_73f19bfa2b4f43e1b7db672923e0d655.pdf
    • https://static.usrfiles.com/ugd/b8c837_65935f0f44a7452cbeb395df8629532b.pdf
    • https://static.usrfiles.com/ugd/2f7815_19283ae42d0b44bf99da8f9a09ed2e9b.pdf
    • https://static.usrfiles.com/ugd/30e015_4254580b9b9b4ae4a1abc76756034a8d.pdf
    • https://static.usrfiles.com/ugd/1849a1_c7efe2330c034b68a22c2e8f95491350.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006df8.bin
bb583c6191aceff4b99be4f77eeb42faad0cc419c72f65e26f0b69782cbe19a6
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DF8 5252 bytes
font_01_sfnt_off00007ff5.bin
5f31191750f55be6ce5ac81950bec4e4462860c2aa6dc528ffe03bd85f4ed746
pdf-font-stream PDF embedded font (sfnt) at offset 0x7FF5 10428 bytes