Malicious PDF — malware analysis report

Static analysis result for SHA-256 2cfca04f463f2197…

MALICIOUS

PDF

40.5 KB Created: 2020-08-31 01:35:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 35ef4704009b38a98c12527bdf32bb1b SHA-1: 9b33d3676c581ecddfc9e512d115abfec31d41e3 SHA-256: 2cfca04f463f21970dae2ee649073504fd55309defa2f2e2e81e15d1079fbc3a
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which are hosted on Shopify and appear to be part of a link farm designed to improve search engine rankings. One of these links, https://ttraff.ru/wix?keyword=what+is+sensory+imagery, is identified as a malicious redirector. The document body, though partially corrupted, contains text related to 'sensory imagery' and the authoring application 'wkhtmltopdf', suggesting a lure to disguise the malicious links. The ML classifier strongly supports the malicious verdict.

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/wix?keyword=what+is+sensory+imagery
    • https://cdn.shopify.com/s/files/1/0432/6775/2100/files/kufalovuduzudide.pdf
    • https://cdn.shopify.com/s/files/1/0432/9101/7374/files/reglas_del_memorama_en_ingles.pdf
    • https://cdn.shopify.com/s/files/1/0429/1588/9305/files/criminal_behavior_psychology.pdf
    • https://static.usrfiles.com/ugd/c0b427_498daeb4927342c0a0bba28ee0ca094c.pdf
    • https://static.usrfiles.com/ugd/3649d2_1302c7894b8f4b53b5afbfa2977e2f98.pdf
    • https://static.usrfiles.com/ugd/6a22cb_b25345f5a2434f87a0a9b01c4fc0950b.pdf
    • https://static.usrfiles.com/ugd/5438e3_570a55b9b78a4ac99486d14f0c3de5a2.pdf
    • https://static.usrfiles.com/ugd/bd5c68_793f667f56184007b0922d347a41f88e.pdf
    • https://static.usrfiles.com/ugd/c1615c_a7781616e6e948759288eef13c585f15.pdf
    • https://cdn.shopify.com/s/files/1/0430/4430/7098/files/gogokerere.pdf
    • https://cdn.shopify.com/s/files/1/0437/5596/2522/files/bootstrap_form_border_style.pdf
    • https://cdn.shopify.com/s/files/1/0429/9961/1555/files/19034389907.pdf
    • https://cdn.shopify.com/s/files/1/0429/3846/6467/files/8497978118.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_off000061d2.bin
330e023d0b689aa8482917d7a7d5601e4ea11d6bd0b33b4d7c7e1728e8079022
pdf-font-stream PDF embedded font (sfnt) at offset 0x61D2 5180 bytes
font_01_sfnt_off00007353.bin
e9164a62f5aed7f38059773d8cefaaa91f2424f350e64c033eefec5248c70860
pdf-font-stream PDF embedded font (sfnt) at offset 0x7353 10076 bytes