Malicious PDF — malware analysis report

Static analysis result for SHA-256 145873b43d622420…

MALICIOUS

PDF

42.3 KB Created: 2020-07-17 19:02:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: 24f00f95f3f8fcf407c851933dd0be26 SHA-1: 095c11ef581b74fd43e51d86782772c2f0ed845a SHA-256: 145873b43d6224203d1d081d03030afe794cd8e4333baaaac38b72037e3dcea2
194 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links designed to appear as academic resources, but which actually lead to a redirector and then to other PDF files. This technique is commonly used for SEO poisoning and phishing, aiming to drive traffic to malicious sites or distribute malware. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

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.cc/wb?keyword=engineering%20science%20n3%20question%20papers%20and%20memos%20pdf%202016 In PDF document text
    • http://files.sjrb-online.com/uploads/1/3/0/8/130813663/b4a8c5cf1a2267.pdfIn PDF document text
    • http://files.livingwordpub.com/uploads/1/3/0/7/130738504/1538540.pdfIn PDF document text
    • http://files.summerlandchurchoflight.org/uploads/1/3/1/3/131383842/166ba4bf.pdfIn PDF document text
    • http://files.imagebunny.com/uploads/1/3/1/4/131437061/zexolapesadix.pdfIn PDF document text
    • http://files.handymanservicesanchorage.com/uploads/1/3/0/7/130740033/rivopuvibipipiv-bozexeve-dilufazolototu-gitabopu.pdfIn PDF document text
    • http://files.existentialbiker.com/uploads/1/3/2/3/132303099/gobob.pdfIn PDF document text
    • http://files.epsteinbarrvirusnaturalhealth.com/uploads/1/3/0/7/130738821/5100723.pdfIn PDF document text
    • http://files.columbusasphaltservices.com/uploads/1/3/0/8/130813546/5375164.pdfIn PDF document text
    • http://files.fayettedentalaesthetics.com/uploads/1/3/0/8/130813988/kibina.pdfIn PDF document text
    • http://files.islandfishingkauai.com/uploads/1/3/1/4/131453651/63e4b6b45.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://sutaxirelib345322610.files.wordpress.com/2020/07/gadorezamizeziwav.pdfIn PDF document text
    • https://nalupewinebo.files.wordpress.com/2020/07/xuniloro.pdfIn PDF document text
    • https://pilimiridap.files.wordpress.com/2020/07/60004741999.pdfIn PDF document text
    • https://tejunif.files.wordpress.com/2020/06/31160693914.pdfIn PDF document text
    • https://medidiri.files.wordpress.com/2020/06/vabap.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1278/4277/files/30603953521.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8356/3162/files/66247595423.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/7148/0742/files/bifowetake.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/2778/4099/files/35368695575.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/zigomotixiwututorevibalu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/5962/5627/files/89985592217.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/4309/4677/files/zixatupuribevemajowoj.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_off000060ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x60ED 6052 bytes
SHA-256: 8aa6dbb75595ee93091aeab179f42a30b1f64baf80a315722842ce33307139af
font_01_sfnt_off00007566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7566 10816 bytes
SHA-256: bd2bbbc1309300113e28ec51ec802353a7321bdc519886263aa30eb5c1db2db1