Malicious PDF — malware analysis report

Static analysis result for SHA-256 521401b6075e249e…

MALICIOUS

PDF

40.5 KB Created: 2020-11-04 19:50:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d0860ab5d2591e58c7de7252d9948777 SHA-1: 954e39cb96aac6ca7d90ccad4c2e293952af791d SHA-256: 521401b6075e249e71d0bbf98c3e3baef9a6d630fe6f2afc8754e212b0521527
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to suspicious or unknown domains, indicating a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains the URL https://cctraff.ru/aws?keyword=study+guide+4+accounting, which is flagged as a known malicious redirector. This suggests the PDF is part of a phishing or malware distribution campaign.

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://cctraff.ru/aws?keyword=study+guide+4+accounting
    • https://kolivobaka.weebly.com/uploads/1/3/4/5/134500933/tanaxewasiwudab_sudidiba.pdf
    • https://zukezima.weebly.com/uploads/1/3/4/3/134345014/fabulobisukab.pdf
    • https://cdn-cms.f-static.net/uploads/4370068/normal_5f92358d3f783.pdf
    • https://cdn-cms.f-static.net/uploads/4410000/normal_5f9ea526b7503.pdf
    • https://cdn-cms.f-static.net/uploads/4368741/normal_5f964399c0a8c.pdf
    • https://cdn-cms.f-static.net/uploads/4369183/normal_5f8d430d1634c.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/7655442f-b958-4fd6-bbdd-db264f1f386b/zuzapajufuz.pdf
    • https://s3.amazonaws.com/vavale/vadewejijijekedu.pdf
    • https://uploads.strikinglycdn.com/files/8b5aaedb-b13e-4533-af0a-1fec5e577d0c/44987230814.pdf
    • https://uploads.strikinglycdn.com/files/b277c25f-b92a-4ba0-ac99-a0e6c3e6881d/6938424027.pdf
    • https://s3.amazonaws.com/fizup/28590252250.pdf
    • https://uploads.strikinglycdn.com/files/0f7b9d8d-4f79-4ba0-a0d9-274e7d88ab8a/21343451425.pdf
    • https://uploads.strikinglycdn.com/files/1c8f5dd4-415a-4739-af99-4fb2612ad66d/badaje.pdf
    • https://uploads.strikinglycdn.com/files/4fc88e74-0f37-4e42-96ca-e4aa7588e03f/fobefudadefudabibuji.pdf
    • https://uploads.strikinglycdn.com/files/e399a4a8-927f-4f59-aac5-898095248ee6/dutukalox.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_off000060ee.bin
7aafca6106d1df18ca89345b081e7b70b6844a1fadc3c6d2038238deadd824b7
pdf-font-stream PDF embedded font (sfnt) at offset 0x60EE 5096 bytes
font_01_sfnt_off0000726a.bin
9daf5033259cd05063bfdc177adc921339fedf58884c906ad45b8aa176b55d19
pdf-font-stream PDF embedded font (sfnt) at offset 0x726A 10288 bytes