Malicious PDF — malware analysis report

Static analysis result for SHA-256 fef6ab28449ca8cb…

MALICIOUS

PDF

35.6 KB Created: 2020-09-10 02:55:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fd72d3b52c4bdb3aaed42a67ef2c5eda SHA-1: 52445d0cdfd1ace7de9a715534584a96c60d5b40 SHA-256: fef6ab28449ca8cbce31b2010760eb8ec3a5856717ab6f6692d407812baf6f98
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, disguised as a user manual. The ML classifier strongly indicated maliciousness. The document body, though heavily obfuscated, contains text related to 'Back- ups xs 1500 user manual' and includes the malicious URL, reinforcing the lure. The presence of numerous links to external PDFs, many hosted on static.usrfiles.com, suggests a link farm or SEO poisoning tactic to increase visibility.

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.link/wix?keyword=back-+ups+xs+1500+user+manual
    • https://static.usrfiles.com/ugd/e8506d_7fb3171f92e840f2a8cfaf748b432970.pdf
    • https://static.usrfiles.com/ugd/9cb927_fb6d96c12981484780fefee41319da1d.pdf
    • https://static.usrfiles.com/ugd/3ab5ed_e3b38571eb4446dea3a1b335f8f26942.pdf
    • https://static.usrfiles.com/ugd/7f929b_4406406c47124256951aa51906766124.pdf
    • https://static.usrfiles.com/ugd/7a13df_ae9fe0cfbcad4bd3952faebac2d4ef27.pdf
    • https://static.usrfiles.com/ugd/7d21c0_49c33ba555804372985b761c314bd394.pdf
    • https://cdn.shopify.com/s/files/1/0433/7316/6744/files/zurareronujosomibul.pdf
    • https://cdn.shopify.com/s/files/1/0433/0301/0459/files/iq_test_online_free_with_answers.pdf
    • https://cdn.shopify.com/s/files/1/0430/3768/7962/files/futon.pdf
    • https://static.usrfiles.com/ugd/a3b54b_f2fd2db9b6dd4e279252116e7902e7aa.pdf
    • https://static.usrfiles.com/ugd/eed56f_c9e2ff5f26864e45a6be30a735291d86.pdf
    • https://static.usrfiles.com/ugd/c34aa9_70b00cfe5f59442bb3bf4799c7d12402.pdf
    • https://static.usrfiles.com/ugd/f6a907_a4e0235e1bb447cfbc1dab24de6a78d0.pdf
    • https://static.usrfiles.com/ugd/b8c837_4fafe1556de04878b0877aa3f90d2071.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_off00004c5a.bin
59000dc0c3fe8126b48f9cf83d1a4514697acf419dd1c1a39adbaacd7ae00307
pdf-font-stream PDF embedded font (sfnt) at offset 0x4C5A 5608 bytes
font_01_sfnt_off00005f6e.bin
e20fc5b7afc92080847cc122130e19343a11a18639ad798aafacd5fae8abfc44
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F6E 10080 bytes