Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5b6a3837dd88ad8…

MALICIOUS

PDF

41.5 KB Created: 2020-08-12 21:32:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2381ef69403fb15bd3152b7edde183bc SHA-1: 0f2c2499dee2cab30218741a692e69aee00d3ed5 SHA-256: d5b6a3837dd88ad846fd5e367810b1f76ce858abd71f1d0854923458a707a178
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, which is disguised as a document about 'Theseus and the labyrinth'. The document also contains a large number of links to other PDFs hosted on Shopify, likely part of a link farm to improve search engine ranking for malicious content. The ML classifier 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.ru/wb?keyword=theseus%20and%20the%20labyrinth%20pdf
    • http://files.flbutterflyeffectboutique.com/uploads/1/3/1/3/131383943/5370686.pdf
    • http://files.authortaradawn.com/uploads/1/3/1/6/131606186/xosekibip_pewaximuwakewal_dazekezo_dusoku.pdf
    • http://files.philmartin.co.uk/uploads/1/3/0/8/130815115/nibubelekekofir-pirenevenofim-gubufan-bidakiseramodow.pdf
    • http://buwumuf.dawgpoundfanclub.com/uploads/1/3/0/8/130874457/fodeworosepu.pdf
    • http://files.stmaryscadillac.org/uploads/1/3/2/6/132683259/bojopa.pdf
    • https://cdn.shopify.com/s/files/1/0432/5575/9011/files/83419837189.pdf
    • https://cdn.shopify.com/s/files/1/0429/1526/6713/files/86077615008.pdf
    • https://cdn.shopify.com/s/files/1/0431/7177/4615/files/nisabusupixo.pdf
    • https://cdn.shopify.com/s/files/1/0434/7602/5497/files/discrete_probability_distribution.pdf
    • https://cdn.shopify.com/s/files/1/0437/0844/8919/files/83565937784.pdf
    • https://cdn.shopify.com/s/files/1/0435/0600/8216/files/funog.pdf
    • https://cdn.shopify.com/s/files/1/0432/2318/7614/files/56258075976.pdf
    • https://cdn.shopify.com/s/files/1/0434/0006/9285/files/96196284590.pdf
    • https://cdn.shopify.com/s/files/1/0430/5335/1066/files/82756419491.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_off000063a9.bin
1ac7206f67261fd02ac50309de264a52d1d0403d6fef10dcf31704abad704d7e
pdf-font-stream PDF embedded font (sfnt) at offset 0x63A9 5320 bytes
font_01_sfnt_off000075ac.bin
c5d140677074609f5493d5540054b28454a0387c987d674b3137a2b9ccade0d4
pdf-font-stream PDF embedded font (sfnt) at offset 0x75AC 10376 bytes