Malicious PDF — malware analysis report

Static analysis result for SHA-256 82ecb539a5811c0a…

MALICIOUS

PDF

47.4 KB Created: 2020-11-07 18:45:46 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 932ef21707c04066acd20941f64816b7 SHA-1: 3c0ff270ec74e7d7e4f5b40d4b5b30679859141e SHA-256: 82ecb539a5811c0ad94d704a2e46ac579bd391f481a14d06013b511d4e3feb09
76 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a lure related to 'math worksheets land answer keys' and embeds a URL that redirects to a suspicious domain. This suggests a phishing attempt designed to lead users to a malicious site. The ML classifier strongly indicates maliciousness, and the embedded URL is a primary indicator of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://traffnew.ru/123?keyword=math+worksheets+land+answer+keys PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4367642/normal_5f9a2ee2d1c98.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448094/normal_5f9e38c4ccd1e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380859/normal_5f990c3411f3a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://pavegokeji.files.wordpress.com/2020/11/atharvashirsha_kannada.pdfIn PDF document text
    • https://s3.amazonaws.com/wejalixex/4_lines_poem_on_moon_in_hindi.pdfIn PDF document text
    • https://s3.amazonaws.com/roxawo/dinatapikamegekapejuwu.pdfIn PDF document text
    • https://s3.amazonaws.com/xubifupi/is_christianity_a_religion.pdfIn PDF document text
    • https://s3.amazonaws.com/pizexopenaxu/practical_electronics_for_inventors.pdfIn PDF document text
    • https://puverak.files.wordpress.com/2020/11/65236564333.pdfIn PDF document text
    • https://mudupetem.files.wordpress.com/2020/11/60700338149.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007a7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7A7F 5176 bytes
SHA-256: 0b1159e1fe4f60e106b6b087df5717e40b162fd63b7292976e51d9dca6a81bd6
font_01_sfnt_off00008c30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8C30 10840 bytes
SHA-256: a4e2f80c4ee5343fd9edb4f43d8160550ffbee590181f2eb9f904beac63cf4a4