Malicious PDF — malware analysis report

Static analysis result for SHA-256 bdfa4e624d7e0443…

MALICIOUS

PDF

35.4 KB Created: 2020-08-13 15:46:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f092b79b4c4e0db0ef0cfa428da2c217 SHA-1: 4e9814d70d880200089023e670c894ab224d853a SHA-256: bdfa4e624d7e044355dfbe28dcbba0569622114d64632e5244aca73feef437db
152 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, which is likely intended to lead the user to a malicious site. The document body, though heavily obfuscated, contains the same URL and a large number of other URLs, many hosted on cdn.shopify.com, suggesting a link farm or SEO poisoning tactic. The ML classifier 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/pify?keyword=aristoteles+metafisica+pdf+gredos
    • http://files.aplusoftexas.com/uploads/1/3/0/7/130740429/9395144.pdf
    • http://xivepoto.salvationarmyjustice.ca/uploads/1/3/0/7/130776485/3108596.pdf
    • http://jalapujim.janrosenberg.com/uploads/1/3/1/3/131383314/ad509ca8.pdf
    • http://files.bzdickstudio.com/uploads/1/3/1/3/131380480/xoxuvawu.pdf
    • https://cdn.shopify.com/s/files/1/0439/9045/0334/files/9646979918.pdf
    • https://cdn.shopify.com/s/files/1/0428/8489/0790/files/40191222478.pdf
    • https://cdn.shopify.com/s/files/1/0434/2562/8327/files/for_each_loop_javascript.pdf
    • https://cdn.shopify.com/s/files/1/0433/8984/5671/files/export_3d_to_step.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/gejazopemovaro.pdf
    • https://cdn.shopify.com/s/files/1/0433/4750/9416/files/jetusafabivorula.pdf
    • https://cdn.shopify.com/s/files/1/0429/5737/3589/files/definition_du_manager.pdf
    • https://cdn.shopify.com/s/files/1/0437/6113/9861/files/work_experience_certificate_letter.pdf
    • https://cdn.shopify.com/s/files/1/0429/4184/1571/files/brilliant_green_bile_broth.pdf
    • https://cdn.shopify.com/s/files/1/0432/2741/4696/files/indent_in_excel.pdf
    • https://cdn.shopify.com/s/files/1/0428/7270/1095/files/78457588684.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_off0000481b.bin
a041d5b53dfa95a3be56e6a1ae4ede775ed2a240fecd8436c0ddd0bea7b95549
pdf-font-stream PDF embedded font (sfnt) at offset 0x481B 5464 bytes
font_01_sfnt_off00005a98.bin
310471edd576723c76b15cd2da1cc29790b526323d9b741a5c88c36bd6e1d177
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A98 10992 bytes