Malicious PDF — malware analysis report

Static analysis result for SHA-256 85c9374ad27a2ff8…

MALICIOUS

PDF

40.4 KB Created: 2020-08-19 21:57:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7c79218dd49b90351da94ad4d8139540 SHA-1: 7ad0fcc87970c627ea0b1f0b5f288066db00e6ba SHA-256: 85c9374ad27a2ff82aba2157e69aec1d8706a01ccfff00d381a950017017e5d0
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious due to its function as a PDF redirector and link farm. It contains numerous embedded URLs, with one pointing to known malicious infrastructure at `ttraff.ru`. The document body, though heavily obfuscated, also contains this malicious URL and other links hosted on Shopify, suggesting an attempt to distribute content or lure users to external sites. The ML classifier strongly supports the malicious verdict.

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=frying+pan+shoals+fishing+report
    • http://fujiru.kahnawakeballhockeyleague.com/uploads/1/3/0/7/130739579/7454539.pdf
    • http://xixobonej.iiamartmodels.com/uploads/1/3/1/4/131438464/52aee64c.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/3346/7808/files/lefepetaraf.pdf
    • https://cdn.shopify.com/s/files/1/0434/6193/5261/files/lua_for_loop.pdf
    • https://cdn.shopify.com/s/files/1/0428/9177/2063/files/vacuna_neumococica_conjugada.pdf
    • https://cdn.shopify.com/s/files/1/0443/8091/3830/files/timex_nature_sounds_alarm_clock_manual.pdf
    • https://cdn.shopify.com/s/files/1/0437/1513/3605/files/14114393656.pdf
    • https://cdn.shopify.com/s/files/1/0431/1282/4986/files/sri_bhagavatam_telugu.pdf
    • https://cdn.shopify.com/s/files/1/0429/7588/7523/files/87134682411.pdf
    • https://cdn.shopify.com/s/files/1/0432/7663/2217/files/foxufugibujem.pdf
    • https://cdn.shopify.com/s/files/1/0433/5602/9093/files/2008_scion_xd_repair_manual.pdf
    • https://cdn.shopify.com/s/files/1/0431/5355/5610/files/biraxe.pdf
    • https://cdn.shopify.com/s/files/1/0439/2815/8363/files/23547549002.pdf
    • https://cdn.shopify.com/s/files/1/0430/7176/6677/files/69586602796.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_off00006000.bin
6be72c810efee2fb8f3eb55aff2688d2ab93dcb1342eaa975cd488127fc95c43
pdf-font-stream PDF embedded font (sfnt) at offset 0x6000 5220 bytes
font_01_sfnt_off000071c6.bin
d38240ea2dbd51cf68640e75245018aefac437aef7da01ff2a2316168bd01324
pdf-font-stream PDF embedded font (sfnt) at offset 0x71C6 10340 bytes