Malicious PDF — malware analysis report

Static analysis result for SHA-256 621fc4564db17ece…

MALICIOUS

PDF

43.2 KB Created: 2020-11-01 16:02:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2a49bddb3b115c0e3da306db795690bb SHA-1: 73a4245e02d1858ae640ac6730f0b78277107259 SHA-256: 621fc4564db17ece158fe4bdae9c23e74f78b2abcd5e78c869a6fab1624b13da
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 known malicious redirector infrastructure. The document body, though heavily obfuscated, contains a URL that is also present in the heuristics, indicating a deliberate attempt to lead users to malicious sites. The ML classifier strongly supports the malicious nature of this PDF.

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/123?keyword=2012+ap+statistics+free+response+answers
    • https://cdn-cms.f-static.net/uploads/4365653/normal_5f8711e2f17c2.pdf
    • https://goraworozegisu.weebly.com/uploads/1/3/4/3/134324811/60e37.pdf
    • https://wepugimi.weebly.com/uploads/1/3/1/0/131070973/4333548.pdf
    • https://cdn-cms.f-static.net/uploads/4420468/normal_5f98ce376b51d.pdf
    • https://cdn-cms.f-static.net/uploads/4383582/normal_5f91a0383f088.pdf
    • https://beperiguvo.weebly.com/uploads/1/3/4/3/134320750/88562.pdf
    • https://cdn-cms.f-static.net/uploads/4368748/normal_5f89b1f00ff01.pdf
    • https://cdn-cms.f-static.net/uploads/4406208/normal_5f9815a142b3e.pdf
    • https://depufavekozumel.weebly.com/uploads/1/3/4/0/134017714/7a9dd7eb.pdf
    • https://niviraxaxupo.weebly.com/uploads/1/3/4/4/134469592/2728781.pdf
    • https://cdn-cms.f-static.net/uploads/4417312/normal_5f9cfbfa3aa5b.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/cac850de-1b8e-4dec-834e-3090143bc378/69695728746.pdf
    • https://s3.amazonaws.com/henghuili-files/zimezelobanunafenotezeba.pdf
    • https://uploads.strikinglycdn.com/files/40887e88-d951-44ae-a106-89ca16fc0813/nibuzek.pdf
    • https://s3.amazonaws.com/mipeboro/ffxiv_weaver_leve_guide.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_off0000695b.bin
faedea226cad0ecc7234713b0ea137cce34cf66dc9330b3f56dfedb9ec610542
pdf-font-stream PDF embedded font (sfnt) at offset 0x695B 5300 bytes
font_01_sfnt_off00007b87.bin
cd9f51fe694913efe98077cace45c95e0321151bc1b92a5512d06573cc456a3c
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B87 10656 bytes