Malicious PDF — malware analysis report

Static analysis result for SHA-256 839df4a21f64f43e…

MALICIOUS

PDF

40.3 KB Created: 2020-09-08 14:39:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8aba15c4e396b5c6a3adedb809d38db5 SHA-1: e86af056c9fea4f9a763c8011186bb924aec4f5f SHA-256: 839df4a21f64f43e500b119a17fb8a600ee4ad3433333e968ba040f82fc88734
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link farm and a malicious redirector URL, disguised as a document about Boyle's law problem solving. The ML classifier strongly indicated maliciousness. The embedded URLs likely lead to further malicious content or phishing pages, and the document itself is likely a lure to initiate a phishing or malware download chain.

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.club/wix?keyword=boyle%2527+s+law+problem+solving+with+answers
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0436/1961/4884/files/jifuzafufafudovu.pdf
    • https://cdn.shopify.com/s/files/1/0430/1537/2949/files/89716872286.pdf
    • https://cdn.shopify.com/s/files/1/0433/9289/3095/files/kotalozumapowejujegiv.pdf
    • https://cdn.shopify.com/s/files/1/0434/8005/5974/files/79351230389.pdf
    • https://cdn.shopify.com/s/files/1/0434/4945/0663/files/conundrum_problems_and_answers.pdf
    • https://cdn.shopify.com/s/files/1/0440/8963/9077/files/3896176179.pdf
    • https://cdn.shopify.com/s/files/1/0449/7945/4111/files/cerere_demisie.pdf
    • https://cdn.shopify.com/s/files/1/0427/5326/1724/files/caballo_de_troya_9_can.pdf
    • https://static.usrfiles.com/ugd/5dc3ca_52ed8690d1d84564a1928be8a55fd072.pdf
    • https://static.usrfiles.com/ugd/c0fca2_e14e7a87a62641b8a08f45940b988fef.pdf
    • https://cdn.shopify.com/s/files/1/0432/0142/9662/files/zafavofukiwavejeb.pdf
    • https://cdn.shopify.com/s/files/1/0460/3694/3007/files/mathematical_statistics_with_applications_7th_edition_wackerly.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_off00005d15.bin
99ddfae73cc95f511eb9ae0ed2b9ce20efdf914822f84ba74530bd7ab906a59f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D15 5708 bytes
font_01_sfnt_off00007087.bin
32eb65e14abfa2e59bcf02e2724db8369e3953fd81cfcd87a6676f26a10deaef
pdf-font-stream PDF embedded font (sfnt) at offset 0x7087 10660 bytes