Malicious PDF — malware analysis report

Static analysis result for SHA-256 64c19f99cec7e733…

MALICIOUS

PDF

47.4 KB Created: 2020-08-30 07:22:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e88c66ff52272bb1e8df19ddd313c7df SHA-1: b516db4352ea6ac8897871edeb39d8605805610c SHA-256: 64c19f99cec7e7330c9fb23edd51350eb13263d5a9bc2dba78af1723fc90da18
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded links, with one prominently featuring a URL that is flagged as a malicious redirector. The document body, though heavily obfuscated, includes text that appears to be a lure for a 'skills assessment'. The presence of numerous external PDF links, many pointing to benign content, suggests a link farm or SEO poisoning tactic to distribute the malicious URL. 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.ru/wix?keyword=vb+mapp+early+echoic+skills+assessment
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_851f96e37cb9445dbee9da648d5e6290.pdf
    • https://static.usrfiles.com/ugd/b65acf_42b738b6cffb4fdbbd255e3b9cc56c6c.pdf
    • https://static.usrfiles.com/ugd/173616_920dffbe789f4393afb5867a0e070cbf.pdf
    • https://static.usrfiles.com/ugd/b8c837_6d44194bb61a466691d258b59782fb6d.pdf
    • https://static.usrfiles.com/ugd/b8c837_311c22bcd3a346988ed7ac3f2868541d.pdf
    • https://static.usrfiles.com/ugd/3b47cb_2e1928773f464d4fba668f03436c0abb.pdf
    • https://cdn.shopify.com/s/files/1/0429/6795/7660/files/59287212009.pdf
    • https://cdn.shopify.com/s/files/1/0428/8148/2919/files/wusopubogabizubejegikote.pdf
    • https://cdn.shopify.com/s/files/1/0437/2421/0326/files/automatic_stabilizer_circuit_diagram.pdf
    • https://cdn.shopify.com/s/files/1/0431/6430/3522/files/sisoxozolepoxed.pdf
    • https://static.usrfiles.com/ugd/b8c837_8341c4b656a844e8b5af283556d54cae.pdf
    • https://static.usrfiles.com/ugd/2ac701_ab233687a2b740c5af2522fe8f5b13ef.pdf
    • https://static.usrfiles.com/ugd/b8c837_7d37cacaac1b4d3b83e38fa871d2ed5f.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_off00007b3c.bin
def81c225057e5a8bc0191b63dde478453e48494328c50d6cad9ae0ba0277ce9
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B3C 5444 bytes
font_01_sfnt_off00008d98.bin
b13f963eac537c5457c3913f9ca95a083031988c8a859509b7a1199e7fd14d4e
pdf-font-stream PDF embedded font (sfnt) at offset 0x8D98 10384 bytes