Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b27ea68b37438fe…

MALICIOUS

PDF

39.0 KB Created: 2020-10-15 03:49:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 4c2c7f7eb14f23ca54d25c6d779e1726 SHA-1: 7a49f68847073566e45a83066f7c5de1998e071b SHA-256: 6b27ea68b37438fe4e094e076199868dba9c5e013c19c14542e7bdc0af8f1158
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains multiple embedded links, one of which points to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains the URL that is also present in the heuristic findings, suggesting it is intended to lure the user to malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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 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://cctraff.ru/strik?keyword=modal+verb+multiple+choice+exercises+pdf In PDF document text
    • https://site-1038382.mozfiles.com/files/1038382/wudobelolukujizivupin.pdfIn PDF document text
    • https://site-1042198.mozfiles.com/files/1042198/69837846190.pdfIn PDF document text
    • https://site-1037075.mozfiles.com/files/1037075/tosagunuwakumadanonejedo.pdfIn PDF document text
    • https://site-1037858.mozfiles.com/files/1037858/zebojigapinopawubizeru.pdfIn PDF document text
    • https://site-1039481.mozfiles.com/files/1039481/jadivugonurezojaramadeba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367646/normal_5f8783f18671d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366311/normal_5f87696e91553.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365570/normal_5f8713e47f82c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365542/normal_5f87868ac2c7e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365635/normal_5f8752bb5d1c6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366408/normal_5f8725c66d2bb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365636/normal_5f87801f43a76.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366973/normal_5f8781cd66008.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368221/normal_5f879c6016c09.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366029/normal_5f86fa4b2ec80.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366350/normal_5f8778de4625d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366057/normal_5f8788aeafbfb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366024/normal_5f87814bbcacc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365580/normal_5f872fe78c5ec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366031/normal_5f8782f8d1138.pdfIn PDF document text
    • https://site-1041946.mozfiles.com/files/1041946/35952507225.pdfIn PDF document text
    • https://site-1039924.mozfiles.com/files/1039924/kexunep.pdfIn PDF document text
    • https://site-1048529.mozfiles.com/files/1048529/38621455665.pdfIn PDF document text
    • https://site-1038961.mozfiles.com/files/1038961/63687123735.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/ac95f6d3-2240-4bee-abf2-cc4f7ebd70c5/42051659041.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55f5891a-bf89-4365-87a7-70f6752ffdfb/70334691872.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ad0d7a0-8d5e-45ba-8708-ea2ecbf408d4/tosigewapovose.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/873df42a-b26a-4c2b-94a0-58686a3eac19/sarim.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1055ad0c-ff9a-490f-9a2b-0160c38ce9fa/9436469226.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_off0000575d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x575D 5668 bytes
SHA-256: daff3e535acfb6cd6ed5ab9b3db26c50d408233adcf4844c399a26727a420609
font_01_sfnt_off00006a92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6A92 10392 bytes
SHA-256: 24c643ae4aee7ab07cc3a0ff281112a9333fd4842a049a0216b5f1c1c2f27caa