Malicious PDF — malware analysis report

Static analysis result for SHA-256 af56279a5894ba27…

MALICIOUS

PDF

40.5 KB Created: 2020-08-30 11:28:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f051b7af81cfb1dbb5732204691e17fd SHA-1: a7c19cfff2810a83c10d3ae68dae794132feeecf SHA-256: af56279a5894ba27cc315badf97ddbdf3510228ff44f9b60a5106b392d91536f
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of embedded links, many of which point to Shopify-hosted PDF files, suggesting a link farm for SEO manipulation. One of these links, https://ttraff.cc/wix?keyword=questions+from+a+worker+who+reads, is identified as a known malicious redirector. The ML classifier also strongly flagged this PDF as malicious. The document body itself is heavily obfuscated and contains the same URLs.

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/wix?keyword=questions+from+a+worker+who+reads
    • https://cdn.shopify.com/s/files/1/0430/0167/5939/files/48862298151.pdf
    • https://cdn.shopify.com/s/files/1/0445/4960/3487/files/creating_android_apps_on_mac.pdf
    • https://cdn.shopify.com/s/files/1/0435/7632/8355/files/kavisuroturogader.pdf
    • https://cdn.shopify.com/s/files/1/0434/6170/5888/files/personal_computer_book.pdf
    • https://cdn.shopify.com/s/files/1/0434/8693/7253/files/ruxetinerozegu.pdf
    • https://cdn.shopify.com/s/files/1/0430/6262/4417/files/vcf_file_to_converter_online.pdf
    • https://cdn.shopify.com/s/files/1/0431/0152/0029/files/kokogefapejidaxufom.pdf
    • https://cdn.shopify.com/s/files/1/0432/8855/9782/files/about_me_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0436/1935/2739/files/degapuloxujilanunole.pdf
    • https://cdn.shopify.com/s/files/1/0433/7985/1414/files/what_makes_love_last_gottman.pdf
    • https://cdn.shopify.com/s/files/1/0432/3042/9352/files/84554580735.pdf
    • https://static.usrfiles.com/ugd/f1d680_15f002cf15c44e2e9cdb173f1fdce99b.pdf
    • https://static.usrfiles.com/ugd/18f527_55b641d1e9fb4bdb8dd49ed265f70f39.pdf
    • https://static.usrfiles.com/ugd/b8c837_b04b151de58545ecbe6dbab3f5d30991.pdf
    • https://static.usrfiles.com/ugd/b8c837_0dbb8c5f67c64c6e89d56df9f1fa27d9.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_off00005f83.bin
f508076fb9898e641ebecdaf848fee5af4f8e2439662a2a83ab9b32eb7dc5a92
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F83 5332 bytes
font_01_sfnt_off00007184.bin
fc33bf71bf9ec1eaac5587aa9d128ebd96c4750110b63e884d083ac8cc3242f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x7184 10072 bytes