Malicious PDF — malware analysis report

Static analysis result for SHA-256 4da835320d66acd5…

MALICIOUS

PDF

78.4 KB Created: 2020-11-03 00:29:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 6891ce05578bfaacdff277152c8fc909 SHA-1: 254969b83a98f6d7f163b19181a939ac8ffbb36a SHA-256: 4da835320d66acd53568b622e00410c7262fd46f16a1d158cbe45d2d2f65193d
194 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK and PDF_SEO_LINK_FARM heuristics. The document body, though partially corrupted, contains text that appears to be a lure for the 'Morehead Cain class of 2020', directing users to a suspicious URL. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • 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.
  • 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=morehead+cain+class+of+2020 In PDF document text
    • https://cdn-cms.f-static.net/uploads/4366348/normal_5f8852cbd3f89.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370269/normal_5f8f65fdf195e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366036/normal_5f86f4291d531.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379859/normal_5f8b1c720f068.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366029/normal_5f87043b3dd4b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366304/normal_5f8730fc8c5ea.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403557/normal_5f9129c118eef.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/3459/1911/files/xozafem.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0499/4839/3624/files/tiperoriwomupujakas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c10c4be-8055-46d3-8fc7-1d729b1114b4/69649915851.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3583ab8e-ffa8-4527-bd0d-2083c618f1a5/cuisinart_coffee_maker_manual.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_off0000f2c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C1 5388 bytes
SHA-256: da7d089d11ece947db61ed26aba6399217b8d58305721c5b470a030a83b6beda
font_01_sfnt_off00010519.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10519 11628 bytes
SHA-256: 8397265be4055d3811336b39457bce286fa445f40e90d7b1b5efa008b332d0fe