Malicious PDF — malware analysis report

Static analysis result for SHA-256 b55bd9324dd74962…

MALICIOUS

PDF

42.9 KB Created: 2020-10-27 20:26:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dbeed5073db32a98c05c41aeaa547af6 SHA-1: 54f72ea98857c798c73fefa51a0d8cf2bb77daf6 SHA-256: b55bd9324dd74962871cd14b4f97bae74df73049b9838398348b0e2f677f2318
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with one identified as a malicious redirector. The document body, though heavily obfuscated, contains a URL that appears to be a lure for educational content, likely to mask the malicious intent. The presence of a malicious redirector and a large number of external links suggests an attempt to drive traffic to potentially harmful sites.

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.link/123?keyword=northstar+5+listening+and+speaking+4th+edition+pdf
    • https://cdn-cms.f-static.net/uploads/4384483/normal_5f8f30a91b248.pdf
    • https://gewosawoma.weebly.com/uploads/1/3/0/7/130739201/9947158b656.pdf
    • https://forunevelaviwa.weebly.com/uploads/1/3/4/3/134392474/9639876.pdf
    • https://gazesomudari.weebly.com/uploads/1/3/1/0/131070071/2f60eef35.pdf
    • https://cdn-cms.f-static.net/uploads/4365607/normal_5f8723ef9bb70.pdf
    • https://cdn-cms.f-static.net/uploads/4371020/normal_5f88434c91b00.pdf
    • https://cdn-cms.f-static.net/uploads/4368748/normal_5f8884ed76565.pdf
    • https://cdn-cms.f-static.net/uploads/4367007/normal_5f879e9239125.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/3464/7445/files/positive_aspects_of_volcanoes.pdf
    • https://cdn.shopify.com/s/files/1/0482/3508/5978/files/vizupaz.pdf
    • https://cdn.shopify.com/s/files/1/0434/0314/9479/files/wiguzuniloteza.pdf
    • https://s3.amazonaws.com/fasanag/ramasalad.pdf
    • https://s3.amazonaws.com/felasorarabipis/counting_worksheets_for_kindergarten_1-_20.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005669.bin
750d1396ea0bf5fbbfb1efa7800930e25a2e400cebbc542b316d66b1e2c172b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x5669 3120 bytes
font_01_sfnt_off0000619e.bin
25642031b7b90ab99474f72b1cfe5400ad41bb6e1c13c535478d066aabea2187
pdf-font-stream PDF embedded font (sfnt) at offset 0x619E 5548 bytes
font_02_sfnt_off00007484.bin
676019b6aa520ce7d00afcaa47d971ec650235e050a4decec77928fc66f3cacc
pdf-font-stream PDF embedded font (sfnt) at offset 0x7484 14636 bytes