Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc78fd83cde4f04e…

MALICIOUS

PDF

39.7 KB Created: 2020-08-10 16:39:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 396a0cadbe34030b4bd0f5196a499ec1 SHA-1: cfe53ea887c742c65d73dd6b45bc34ad453c8d56 SHA-256: bc78fd83cde4f04e1708a633b7244a875667d0c3e957703c24f1539cfa58e210
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Phishing: Spearphishing Attachment T1059.001 Command and Scripting Interpreter: PowerShell

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 references to 'meiosis coloring worksheet pdf', suggesting a lure. The presence of numerous other links to Shopify-hosted PDFs indicates a link farm strategy to improve search engine visibility for malicious content.

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=meiosis+coloring+worksheet+pdf
    • http://files.justwork.ca/uploads/1/3/0/8/130813550/6153779.pdf
    • http://files.thememphisjewel.com/uploads/1/3/1/8/131857540/1167312.pdf
    • http://sidevave.girlsinflight.org/uploads/1/3/2/6/132681394/e8f2fc0bb32.pdf
    • https://cdn.shopify.com/s/files/1/0431/9959/4656/files/87341913080.pdf
    • https://cdn.shopify.com/s/files/1/0429/5504/7068/files/75824792150.pdf
    • https://cdn.shopify.com/s/files/1/0431/5978/1538/files/30986646317.pdf
    • https://cdn.shopify.com/s/files/1/0433/9433/4869/files/7025928306.pdf
    • https://cdn.shopify.com/s/files/1/0434/1802/6142/files/zugodemezipox.pdf
    • https://cdn.shopify.com/s/files/1/0433/5288/3352/files/what_is_nuance_paperport.pdf
    • https://cdn.shopify.com/s/files/1/0429/3967/8886/files/27338433333.pdf
    • https://cdn.shopify.com/s/files/1/0427/8134/3903/files/dedinomemexido.pdf
    • https://cdn.shopify.com/s/files/1/0432/6516/3422/files/84664471240.pdf
    • https://cdn.shopify.com/s/files/1/0433/1700/2405/files/adjectives_word_formation_exercises.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_off00005d3c.bin
0d63a1d32cfcf921c47dabcc064d73d49aa01069ef787ac32fd5d26719921b77
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D3C 5368 bytes
font_01_sfnt_off00006f8f.bin
0c1cde3f87302f5d9e13f08a44de28ed920b2beca1b683d906ed447402ecd797
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F8F 10132 bytes