Malicious PDF — malware analysis report

Static analysis result for SHA-256 11f2b4408030e11c…

MALICIOUS

PDF

52.9 KB Created: 2020-07-10 09:37:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 2f6b149f413c0923019c389cb5f05251 SHA-1: 689bfee45fbf2f1029267aa2890ff43dafeed5bc SHA-256: 11f2b4408030e11c86026026e367c3c70ef999619ffcfea2a07e69796ad78254
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document is designed as a link farm, embedding numerous URLs that redirect to other PDF files, likely for SEO manipulation or to distribute malware. One of the embedded URLs, 'https://ttraff.ru/wb?keyword=time%20dilation%20worksheet%20pdf', is identified as a known malicious redirector. The ML classifier strongly indicated maliciousness, and the document structure suggests an attempt to disguise malicious activity through a large number of external links.

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.ru/wb?keyword=time%20dilation%20worksheet%20pdf In PDF document text
    • http://files.bowlermedical.org/uploads/1/3/1/3/131379781/2803418.pdfIn PDF document text
    • http://files.woodyshticks.com/uploads/1/3/1/3/131379612/ritozo_luwubuvilul_bizifodoli.pdfIn PDF document text
    • http://files.chapel-designs.com/uploads/1/3/0/7/130739699/35ab5c10ec42.pdfIn PDF document text
    • http://files.wildhuntmasks.com/uploads/1/3/0/9/130969608/4290853.pdfIn PDF document text
    • http://files.givingbackjack.com/uploads/1/3/0/8/130873838/lanopuzurozipew.pdfIn PDF document text
    • http://files.rebeccapiercefilms.com/uploads/1/3/2/6/132682861/c5ae1d.pdfIn PDF document text
    • http://files.the-beijingguide.com/uploads/1/3/2/7/132712323/jixunumuvav_najaba_zajizizakizok_munevexaxi.pdfIn PDF document text
    • http://files.kathysrescuecats.com/uploads/1/3/1/4/131408537/saxizusuvilufumabaj.pdfIn PDF document text
    • http://files.gcproviders.com/uploads/1/3/0/9/130969709/fidakix_webeva.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://tagelutusa.files.wordpress.com/2020/07/pijapufepasakona.pdfIn PDF document text
    • https://fogumagitevu.files.wordpress.com/2020/07/82958737755.pdfIn PDF document text
    • https://tegedow.files.wordpress.com/2020/06/pesiwegabifa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/womonevixaxijebuvi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/89832202682.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/pigirerunozekolufis.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/jedajuzosefowi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/62042090741.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tivaluzisezulumavolo.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_off000091ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x91CA 5172 bytes
SHA-256: 4f8cf6a277fdca04b0e2b17546492f46537c217c9b8b6f4430b086a2caef412f
font_01_sfnt_off0000a33a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA33A 10400 bytes
SHA-256: 4dba8af4a19e30d4bfcedf88fb611e616f0b53379cf6713fda8bf7b5bdb4ac65