Malicious PDF — malware analysis report

Static analysis result for SHA-256 abed6ca71f9869b9…

MALICIOUS

PDF

39.4 KB Created: 2020-08-30 04:23:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fc3f5059e3db332b51191fb3a75fbe37 SHA-1: 49ed4c3ec9802a6749b1bd3a55d4656144f19ea2 SHA-256: abed6ca71f9869b916ab8c46cd6a1e4cbf36aaedbe1ed074234eecfa426221a2
152 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and contains a critical heuristic firing for a malicious redirector link. The document body, though heavily obfuscated, contains the same suspicious URL found in the heuristics. The file also exhibits characteristics of a PDF link farm, with numerous embedded URLs pointing to external resources, many of which are hosted on Shopify and usrfiles.com. The primary malicious IOC is the ttraff.ru URL, which is likely used to redirect users to a malicious site.

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=resep+kue+kering+keju
    • https://static.usrfiles.com/ugd/5b604d_75f102f534d445e8b4b0720406d634dd.pdf
    • https://static.usrfiles.com/ugd/b8c837_563bce6c44624919b8f09561690b991b.pdf
    • https://static.usrfiles.com/ugd/9421c8_1c08aa94e091440998e5ea563455160b.pdf
    • https://cdn.shopify.com/s/files/1/0440/8301/9941/files/79569388103.pdf
    • https://cdn.shopify.com/s/files/1/0435/1049/7434/files/gusipowemosekemolisomuno.pdf
    • https://cdn.shopify.com/s/files/1/0431/8180/1629/files/17098094898.pdf
    • https://static.usrfiles.com/ugd/87fdc7_48dda8ee18274aaf9fd818b4fbd8d2a8.pdf
    • https://static.usrfiles.com/ugd/fd3290_e058ebbe33ca46aeb9136a0f287a6587.pdf
    • https://cdn.shopify.com/s/files/1/0431/7950/7880/files/65407744689.pdf
    • https://cdn.shopify.com/s/files/1/0437/9528/4130/files/36027660609.pdf
    • https://cdn.shopify.com/s/files/1/0434/6875/0998/files/80696178465.pdf
    • https://cdn.shopify.com/s/files/1/0428/7276/6631/files/sizega.pdf
    • https://cdn.shopify.com/s/files/1/0434/1478/2104/files/fugulizukigobulur.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_off00005e57.bin
4c318713c384f4f7af9cb49403cf936859630abe8c0221383c6ecbd4d58533b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E57 4892 bytes
font_01_sfnt_off00006f21.bin
69bea5a2e5ca0ff8ebaf7f8e95181dea4fc8424986b9690b33d5dcbd40fe6de0
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F21 9980 bytes