Malicious PDF — malware analysis report

Static analysis result for SHA-256 492a53a868b6ae4f…

MALICIOUS

PDF

40.9 KB Created: 2020-08-29 19:43:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 263129f09d85e016dcf026e4c87c843e SHA-1: 7e0056d9bdddcc5501bfe0ed174a352f7a111b96 SHA-256: 492a53a868b6ae4f292f512b4dd77f4dd57f68e81a39cd487842f3028e19f2fc
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to Shopify domains, which is characteristic of a link farm designed to improve search engine rankings. One of these links, https://ttraff.com/wix?keyword=hamstring+exercise+after+acl+surgery, is identified as a malicious redirector. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is used for malicious redirection.

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.com/wix?keyword=hamstring+exercise+after+acl+surgery
    • https://cdn.shopify.com/s/files/1/0435/5833/8715/files/nubemu.pdf
    • https://cdn.shopify.com/s/files/1/0427/9864/5404/files/96190617905.pdf
    • https://cdn.shopify.com/s/files/1/0435/2301/4824/files/libro_caballo_de_troya_1_para_leer_gratis.pdf
    • https://cdn.shopify.com/s/files/1/0429/5937/2439/files/bafemabinem.pdf
    • https://cdn.shopify.com/s/files/1/0432/6552/3862/files/potikalekuzabesaxafolumi.pdf
    • https://static.usrfiles.com/ugd/b8c837_84db9e038b76482c880203a6b52351f6.pdf
    • https://static.usrfiles.com/ugd/b8c837_76517ad3aae0491997d8781ec65862e6.pdf
    • https://static.usrfiles.com/ugd/ace02d_a2a0b40bc0d74b5dae796a29ebc49d39.pdf
    • https://cdn.shopify.com/s/files/1/0427/7708/4070/files/str-_dn1060_manual.pdf
    • https://cdn.shopify.com/s/files/1/0431/1390/6333/files/47569932378.pdf
    • https://cdn.shopify.com/s/files/1/0431/4664/1570/files/59295404801.pdf
    • https://cdn.shopify.com/s/files/1/0432/0509/9675/files/ccri_drivers_ed.pdf
    • https://static.usrfiles.com/ugd/b8c837_cdfc22dafde64875ada98deafc55b3ca.pdf
    • https://static.usrfiles.com/ugd/b8c837_5b86ac5d3a4c43088823d502d87f9643.pdf
    • https://static.usrfiles.com/ugd/b8c837_7abbe3ac97e94446a9a8ad4482f93da4.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_off00006189.bin
ebe1e47d10a1e3d3f5af1af1d728881647380257451723bb015872d18cd18dd1
pdf-font-stream PDF embedded font (sfnt) at offset 0x6189 5332 bytes
font_01_sfnt_off0000739c.bin
f86d7a6ef92a3b76c22d561b4fccea743121b85a68d58d2e96fe705545aa61bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x739C 10268 bytes