Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a5317db2e0cd5b4…

MALICIOUS

PDF

41.7 KB Created: 2020-07-08 17:02:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: 16b113915e7cd357340a2195bb6cc8d4 SHA-1: 3a9f5cf831fa87e71acfeea1ab51c846b85e6172 SHA-256: 0a5317db2e0cd5b47d0a32eac6332ce632055fd9d635640c2a11ff6f27f60b78
184 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs pointing to various external PDF files hosted on numerous disposable domains. This behavior is indicative of a link farm, likely used for SEO manipulation or to distribute malicious content. The presence of a URL to a known malicious redirector further supports the malicious nature of this document.

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://ttraff.cc/wb?keyword=flashcards%20maker%20pdf In PDF document text
    • http://files.pcochoir.com/uploads/1/3/0/7/130739658/xijofidipej.pdfIn PDF document text
    • http://files.lindyjames-christenson.com/uploads/1/3/1/3/131379612/3953267.pdfIn PDF document text
    • http://files.newyorkstategrandcouncil.com/uploads/1/3/1/4/131437538/bapemo.pdfIn PDF document text
    • http://files.oceanwisejourneys.com/uploads/1/3/0/8/130874647/bojeb.pdfIn PDF document text
    • http://files.purpleinkpublishing.com/uploads/1/3/1/4/131437844/mikofoxaxomojope.pdfIn PDF document text
    • http://files.shine-bu.com/uploads/1/3/1/8/131858481/zuvawozupami.pdfIn PDF document text
    • http://files.counsellingpsychologist.services/uploads/1/3/0/9/130969555/7582248.pdfIn PDF document text
    • http://files.finderskeeperscafe.com.au/uploads/1/3/1/3/131398134/xibokesedi.pdfIn PDF document text
    • http://files.missjordansclassroom.com/uploads/1/3/0/7/130776841/5406440.pdfIn PDF document text
    • http://files.diabetest1ireland.com/uploads/1/3/1/8/131872285/3740429.pdfIn PDF document text
    • http://files.frontrunnerbooks.com/uploads/1/3/0/7/130740127/238d271698fcd5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bijetukexer.files.wordpress.com/2020/06/vejikelodazejisu.pdfIn PDF document text
    • https://vunafafop.files.wordpress.com/2020/07/20213910368.pdfIn PDF document text
    • https://verokizafiwi209368049.files.wordpress.com/2020/07/83602106133.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/74832969368.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/43778875991.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/8007882555.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005447.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5447 4856 bytes
SHA-256: 07763d754c9db3d2b4a2da7457be10f6a51e5217a0d2a87122862815b52eaf24
font_01_sfnt_off000064bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x64BC 9416 bytes
SHA-256: 2ef3c66245935fc73d40eb279b20a0b7b1993f3120606d7df544afe8e87ce88a
font_02_sfnt_off00008534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8534 16096 bytes
SHA-256: 37e7e7e9114bd13ff8332e6897528b8343bfbb4b2dd84d96d31ee0d9080a0a97