Malicious PDF — malware analysis report

Static analysis result for SHA-256 3988940f20f99340…

MALICIOUS

PDF

45.7 KB Created: 2020-10-29 10:50:19 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 7fc11cd0e73f03cde0de7737fbe32ab3 SHA-1: 2e935d52e63fcbed0ec6dad41be499dc584927f4 SHA-256: 3988940f20f99340de4237c6465280cc9e9c7c979d47a798dc26b2bc7f24be64
184 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 disposable hosting or redirector infrastructure, indicating a link farm designed to drive traffic. One critical heuristic identified a link to known malicious redirector infrastructure at 'https://gettraff.ru/123?keyword=crosswind+uhp+tire+review'. The ML classifier also strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the document's structure and embedded URLs suggest a phishing or traffic-driving scheme.

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://gettraff.ru/123?keyword=crosswind+uhp+tire+review In PDF document text
    • https://bilewazivabo.weebly.com/uploads/1/3/2/8/132816117/23757.pdfIn PDF document text
    • https://sepikupi.weebly.com/uploads/1/3/0/7/130738949/9930655.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408333/normal_5f9971004d201.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387427/normal_5f8d858b379d0.pdfIn PDF document text
    • https://sakukavazu.weebly.com/uploads/1/3/1/3/131379729/4118662.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381737/normal_5f9a22b1cc60a.pdfIn PDF document text
    • https://papunagaku.weebly.com/uploads/1/3/1/3/131384156/mofubemibon-gezisebujebigin-puzami.pdfIn PDF document text
    • https://titawijuneve.weebly.com/uploads/1/3/4/0/134012454/fd6d2bcb518d.pdfIn PDF document text
    • https://ziripovopibew.weebly.com/uploads/1/3/0/8/130874468/a5e29d49db6f608.pdfIn PDF document text
    • https://fotejisatowonu.weebly.com/uploads/1/3/2/3/132302873/rojilo.pdfIn PDF document text
    • https://xumusiroti.weebly.com/uploads/1/3/4/3/134321309/xesorurevi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371806/normal_5f968998a5f82.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376357/normal_5f89de684f926.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/1/0496/7307/6892/files/simple_distillation_download.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0502/8138/2046/files/94965147500.pdfIn PDF document text
    • https://s3.amazonaws.com/leguvefu/44041145861.pdfIn PDF document text
    • https://s3.amazonaws.com/gupuso/gejedojuxuxapove.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0494/5575/9527/files/fepelibaxigavugoboz.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0503/2568/4420/files/android_browser_with_flash_built_in.pdfIn PDF document text
    • https://s3.amazonaws.com/sikuva/91539198089.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0497/2773/3940/files/luwikuralibizigifitir.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/4361/8965/files/optelec_clear_reader_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/webipejonavuv/29684915042.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_off00007464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7464 4864 bytes
SHA-256: ae0322a0264a4d7348e8fa9512fb3592b46422aeeb7f6a4a8d8be6ae9d7a0c4c
font_01_sfnt_off000084fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x84FD 10656 bytes
SHA-256: 7d56fd3f7a473190e9158e2726cb28e49eafcdc3bc558805d8b075c4124d801d