Malicious PDF — malware analysis report

Static analysis result for SHA-256 e958482767a05e00…

MALICIOUS

PDF

85.7 KB Created: 2021-04-10 15:51:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 0a4e6e462d62d8f388ffd207f4bc84b9 SHA-1: 93c4d273f04099535b10010d89f5d796894ddeb1 SHA-256: e958482767a05e008400930f3ac7142161db35b6b49db29290b6f9e24ccd27ca
184 Risk Score

Malware Insights

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

The sample is a PDF file flagged by multiple heuristics as malicious, including a critical finding for linking to known malicious redirector infrastructure. The embedded URL 'https://dafemum.ru/strik?utm_term=the+cold+war+begins+apush' is identified as a malicious redirector. While no scripts were explicitly extracted, the PDF structure and the nature of the malicious links suggest an intent to lure users to malicious sites, potentially for phishing or malware delivery, aligning with Spearphishing Attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dafemum.ru/strik?utm_term=the+cold+war+begins+apush In PDF document text
    • https://cdn-cms.f-static.net/uploads/4369191/normal_5fea45459763b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425237/normal_603ce803df985.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416669/normal_5fcfa125c5b11.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453098/normal_603d0b1238203.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374203/normal_5fdae30612599.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385631/normal_6035a82a61a56.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487413/normal_6018a8308e458.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://ravetedenafow.rf.gd/past_simple_vs_present_perfect_exercises_with_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8cd0170e-0af1-41b7-8156-63775be332ea/64076098129.pdfIn PDF document text
    • https://30bb9d03-04f1-4043-8ca4-b11f08dd7d37.filesusr.com/ugd/82ab19_424ce132bc2e40df8f30914fcbbd96eb.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/826bae31-e457-4bdc-8595-325be974a7f8/may_2017_sat_qas_answer_key.pdfIn PDF document text
    • http://joratunezawaxa.epizy.com/agriculture_notes_for_upsc_prelims.pdfIn PDF document text
    • https://923a8ca3-316b-4844-b38f-9bc955ad4852.filesusr.com/ugd/312e0e_269ade44fdfc466cb3daed8df17f28a8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c1a3b52-5896-42a3-81bd-97088b8c8419/torelawufureduruwulutiwiz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/15616690-7917-403f-9522-06490a420395/bekonikojukiduleb.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d9e14b9a-ff74-4d1c-8e08-b5e9e2a7af38/what_is_the_funniest_city_name_in_us.pdfIn PDF document text
    • https://3789e5f8-265e-48cd-8836-241a044b7ceb.filesusr.com/ugd/45ef7e_aa8e5535b1d243849386abb323f2a8bc.pdf?index=trueIn PDF document text
    • http://veguxakafopuvix.epizy.com/what_is_usually_the_penalty_for_breaking_a_lease.pdfIn PDF document text
    • http://xolowabijuboxu.epizy.com/folder_cancer_de_boca.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010856.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10856 5516 bytes
SHA-256: eb16c6cb79b5e54b24ca757e9d5b9ca04acdb73a7fe985cc806147153a715b3d
font_01_sfnt_off00011b11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B11 1716 bytes
SHA-256: 7314a8110a688275e79cb4cd5cd058a9f858becaa7f01fde0a687197ddc85302
font_02_sfnt_off0001239c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1239C 11060 bytes
SHA-256: 1a1182af66d28974b3a17844367e387dc1447c7b4085fff965f32b4d4737985d