Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b661e4ef2fb32aa…

MALICIOUS

PDF

34.8 KB Created: 2020-08-13 13:22:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ec88a44826c5a6dacd1401c2c9ccf19c SHA-1: f833004f3a5a4502c9104eda57357ac01f18781d SHA-256: 6b661e4ef2fb32aa02ca6936a1757e52dbee34a3eac265d367667bc4941f93bf
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded links, many of which point to Shopify domains hosting PDF files, but one critical link redirects to `ttraff.cc`, a known malicious redirector. This suggests a link farm or SEO poisoning tactic designed to drive traffic to malicious infrastructure. 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.cc/wb?keyword=present%20tenses%20review%20worksheet
    • http://files.prezziessugarloaf.com/uploads/1/3/2/7/132740606/niripuz.pdf
    • http://files.zanieducation.com/uploads/1/3/1/4/131437513/9d9337.pdf
    • http://files.gallowayflowers.co.uk/uploads/1/3/0/7/130776603/nivilo-gemovewutibi-zanis-xinorib.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0434/2883/9586/files/33800608436.pdf
    • https://cdn.shopify.com/s/files/1/0431/5129/4619/files/9991302640.pdf
    • https://cdn.shopify.com/s/files/1/0432/0978/5499/files/gexudenapusarilaramuro.pdf
    • https://cdn.shopify.com/s/files/1/0430/4335/6825/files/amplificateur_d_instrumentation_exercice_corrig.pdf
    • https://cdn.shopify.com/s/files/1/0438/6367/0939/files/14061031793.pdf
    • https://cdn.shopify.com/s/files/1/0435/9369/5395/files/pujajizutogive.pdf
    • https://cdn.shopify.com/s/files/1/0430/6763/7922/files/30426102697.pdf
    • https://cdn.shopify.com/s/files/1/0429/5062/3385/files/30650583494.pdf
    • https://cdn.shopify.com/s/files/1/0429/5429/3402/files/75233892633.pdf
    • https://cdn.shopify.com/s/files/1/0431/2439/2087/files/kopekoxinigowep.pdf
    • https://cdn.shopify.com/s/files/1/0430/2408/9242/files/95788519541.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_off00004c2d.bin
71ca21ab6c33cd7252019a319466e37c3da00417e7b06fba8f3952664e75a932
pdf-font-stream PDF embedded font (sfnt) at offset 0x4C2D 4748 bytes
font_01_sfnt_off00005c64.bin
0698b1d7593eabba341f8643bef075691fe94d5fcff1aacb71a1794f976b924b
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C64 10052 bytes