Malicious PDF — malware analysis report

Static analysis result for SHA-256 72897e4a4bbf001b…

MALICIOUS

PDF

43.5 KB Created: 2020-08-21 14:02:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ed6dae696f298224463be8863a27ef95 SHA-1: 7ad06d09f6a496d83da27a438dd13a6ea11edbb0 SHA-256: 72897e4a4bbf001b4f258dfa9ab50c432f66dc88c104f539debb82fe40bb5d32
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to Shopify domains hosting other PDFs, suggesting a link farm for SEO manipulation or to obscure malicious redirects. One critical heuristic identified a link to known malicious redirector infrastructure at `https://ttraff.ru/pify?keyword=carcinoma+nasopharynx+pdf`. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains the same malicious URL and several benign-looking PDF links.

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=carcinoma+nasopharynx+pdf
    • http://buwazaruk.sgttommyskids.org/uploads/1/3/2/7/132741555/xezif.pdf
    • http://gowefib.thorsonpto.org/uploads/1/3/2/6/132696067/9dc36ecc91.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0446/0707/8564/files/headway_elementary_video_worksheets.pdf
    • https://cdn.shopify.com/s/files/1/0432/7764/8027/files/pasar_archivo_a_word_online_gratis.pdf
    • https://cdn.shopify.com/s/files/1/0432/4291/3952/files/5673821039.pdf
    • https://cdn.shopify.com/s/files/1/0436/1977/8723/files/55582596254.pdf
    • https://cdn.shopify.com/s/files/1/0430/9454/0452/files/kamugebobuvasir.pdf
    • https://cdn.shopify.com/s/files/1/0437/3879/2085/files/what_is_a_meta_tag_example.pdf
    • https://cdn.shopify.com/s/files/1/0431/1423/4017/files/21214198793.pdf
    • https://cdn.shopify.com/s/files/1/0429/2732/5343/files/18105564263.pdf
    • https://cdn.shopify.com/s/files/1/0437/6172/9685/files/android_file_transfer_pc_bluetooth.pdf
    • https://cdn.shopify.com/s/files/1/0433/0127/3755/files/banufef.pdf
    • https://cdn.shopify.com/s/files/1/0428/9983/2995/files/komplikasi_pneumonia_pada_anak.pdf
    • https://cdn.shopify.com/s/files/1/0435/6656/3487/files/basic_auditing_principles.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_off00006d51.bin
e7d492d45b737a72ad7b69f7548b87a7b1f0b08f7906eff201f906673a36dea9
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D51 5440 bytes
font_01_sfnt_off00007fa7.bin
f3d6f7c8bd2dbf9f2d76d37de050561bb3117edb762e1ed4703c73f401ee2844
pdf-font-stream PDF embedded font (sfnt) at offset 0x7FA7 9876 bytes