Malicious PDF — malware analysis report

Static analysis result for SHA-256 35a0db0759c85e81…

MALICIOUS

PDF

70.4 KB Created: 2020-10-16 22:23:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: e792184c2df3541b5d7b68f23b5d3ab4 SHA-1: 75e0c32e1b60b1bc96c64fe25497cdaa001b4c11 SHA-256: 35a0db0759c85e81dbf92fc4d7f9ab9a16e727717bc2a0eff97b4c501abb9a78
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged as malicious by an ML classifier and contains numerous embedded links. Several heuristics indicate it functions as a link farm, with many links pointing to disposable hosting and redirector infrastructure, including a known malicious redirector. The document body contains a URL that appears to be part of this link farm.

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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ggtraff.ru/123?keyword=intrusive+thoughts+ptsd+worksheets In PDF document text
    • https://cdn-cms.f-static.net/uploads/4366339/normal_5f870defa78af.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365594/normal_5f89b6573c045.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375341/normal_5f89654f9726d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369633/normal_5f8926ff1aa88.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374700/normal_5f899acf6f562.pdfIn PDF document text
    • https://vogizezadu.weebly.com/uploads/1/3/0/8/130814341/96cac65e4da8.pdfIn PDF document text
    • https://fizolapojola.weebly.com/uploads/1/3/1/3/131383549/wexikusisez-fidujupazoz.pdfIn PDF document text
    • https://pavowojavujide.weebly.com/uploads/1/3/1/3/131398322/6878281.pdfIn PDF document text
    • https://kurikezexiwu.weebly.com/uploads/1/3/0/7/130775092/8857289.pdfIn PDF document text
    • https://jonukejunuxesa.weebly.com/uploads/1/3/1/4/131409236/bf3953.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366354/normal_5f87551b6ead7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373757/normal_5f89113ac7c7a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/de44f4ac-7d81-4f2b-bd3f-730b8210e838/922804007.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/528ce820-a604-47ab-9087-d1754e9a3d2d/nibarisunusebakeruzi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/496610c5-0cdb-4f5b-9554-6b4ed8b6c265/58617898365.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d597cee0-aeb3-41b5-b1b8-7472f79ba1db/sugupusalafuna.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1904ea8d-ec0a-43b0-bf7c-ff6743c9b2a9/45029297648.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/84cf6bda-3519-4831-9466-5bbf9f12a350/64302013784.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d4b7faac-2b86-4049-b54f-8c967a37ec1d/5523435785.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0266/7868/9976/files/48886954652.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0463/4456/8989/files/posafej.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0502/1079/9808/files/mejomowugekikoni.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_off0000d737.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD737 5132 bytes
SHA-256: fe05b9fb60d7495c9b37d72c11a8dc8d2fc21af6079057bbf741462a8549f401
font_01_sfnt_off0000e8bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8BF 10304 bytes
SHA-256: a391ffdd38655267214a99a4e22a2e514a2a25b327fdf0211f396c7a8e7d832e