Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2adfc03f14fd4b2…

MALICIOUS

PDF

73.9 KB Created: 2021-06-10 06:18:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 597709bcc47743a193c9c3a45df7a9fc SHA-1: f1542e0d705656f48b0f7f34319218ed7eaa147a SHA-256: a2adfc03f14fd4b280cc90363d23c3f5a6c972197f14b685b9c4daea3f23fe4f
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of a large number of external links, including a link farm on disposable hosting, strongly suggests a phishing or malware distribution campaign. The document's content appears to be obfuscated or corrupted, but the heuristic findings point towards the exploitation of PDF vulnerabilities to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://chcial.ru/pbw?utm_term=9+unblocked+games PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4403561/normal_600b7970f3d87.pdfIn PDF document text
    • https://nunesevafarub.weebly.com/uploads/1/3/0/8/130874378/c298a484.pdfIn PDF document text
    • https://tumazalewiguta.weebly.com/uploads/1/3/4/7/134755417/nuloxatonujuli-natovad-tixizisixik-regirajujewepu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480162/normal_60c1843676383.pdfIn PDF document text
    • https://gavakemew.weebly.com/uploads/1/3/4/5/134591392/76f46099d7b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426060/normal_604d337a06d58.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453908/normal_604dc95c486eb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469135/normal_6041339bc582d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374954/normal_604ed11c714c0.pdfIn PDF document text
    • https://sitoluvumoroge.weebly.com/uploads/1/3/4/7/134762666/gugagegebumeri-nefirof-tipuka.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4401694/normal_5fe3fb7a31b87.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366407/normal_60173fb9a99ed.pdfIn PDF document text
    • https://mevemedetu.weebly.com/uploads/1/3/1/8/131871578/75a26908e15ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490250/normal_6066d3b2a2492.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4447087/normal_60b32db752285.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/a05f1391-27bd-4955-901d-ec175760d277/91349848217.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11340f29-8e19-45e3-8db0-fbb9ab5549a0/42977284260.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c77b0f25-3c83-4e3a-834d-7ffe4376bd5f/sample_interview_questions_and_answers_for_teacher_applicants.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd222c31-0cff-456a-aa7f-912bea027584/scott_cunningham_books_amazon.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_off0000e466.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE466 5428 bytes
SHA-256: 0996ff9f6f34b3eb2b8a0bf54c47ae8f266a3c5b44cf14ce9d337b61c6d4e594
font_01_sfnt_off0000f6c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C5 10528 bytes
SHA-256: 654c06cefe0ef32daaef19e4f1099c78e6a599e5464efb18be5a260064066b9d