Malicious PDF — malware analysis report

Static analysis result for SHA-256 9adc8f8f1f71d1ba…

MALICIOUS

PDF

75.3 KB Created: 2021-06-08 09:06:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: aebe22fd176cd25f91347af273e577ac SHA-1: 3e84c08a6ca34fce5142487c4931b8f9c645c306 SHA-256: 9adc8f8f1f71d1ba700a2d91dbeaf32e2103744a9fa8e942d4483f324dd9ede3
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution through these linked documents. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, suggesting it was programmatically generated.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://catamma.ru/pbw?utm_term=quantos+litros+de+sangue+um+cavalo+pode+perder PDF link annotation
    • https://vutajavegev.weebly.com/uploads/1/3/4/0/134040502/lagakukaru-tawuwigezo-numogamawazag-vuwixag.pdfIn PDF document text
    • https://lixabexuraluna.weebly.com/uploads/1/3/4/2/134234562/gagigigetagatavevola.pdfIn PDF document text
    • https://wikifepum.weebly.com/uploads/1/3/3/9/133986434/7718698.pdfIn PDF document text
    • https://tazipapanora.weebly.com/uploads/1/3/0/7/130776418/2517144.pdfIn PDF document text
    • https://levoveto.weebly.com/uploads/1/3/4/8/134897684/139974.pdfIn PDF document text
    • https://safubijob.weebly.com/uploads/1/3/2/6/132682970/tamiwokelowosi.pdfIn PDF document text
    • https://linoraza.weebly.com/uploads/1/3/1/4/131437671/fuzajejepaxuxojezado.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://jajafad.pbworks.com/f/old_boy_scout_handbook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/109b003c-4925-4373-93db-4bb66c4f9b9c/55400833546.pdfIn PDF document text
    • http://rimogeto.pbworks.com/w/file/fetch/144427425/sql_server_2008_r2_download_for_mac.pdfIn PDF document text
    • http://pezaloribed.pbworks.com/w/file/fetch/144491010/balanceo_de_ecuaciones_por_metodo_de_tanteo_ejemplos.pdfIn PDF document text
    • http://xovelezid.pbworks.com/f/nujobusuresukopivurimubu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d8e6786-bb8d-4f55-a3ae-836ec5edd490/como_se_dar_bem_na_dinamica_de_grupo.pdfIn PDF document text
    • http://fajopab.pbworks.com/f/what_credit_score_do_you_need_for_fingerhut.pdfIn PDF document text
    • http://jujirafamena.pbworks.com/f/management_of_iron_deficiency_anaemia.pdfIn PDF document text
    • http://molosafokaji.pbworks.com/f/roblox_mod_apk_unlimited_robux_2019_download.pdfIn PDF document text
    • http://mitamugukojo.pbworks.com/f/53997263734.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/397a22ea-abad-48f5-a221-37f3ad9e39ad/xufutakolupijewutosid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3e0f13fc-be0d-468c-b72f-7117204c649b/what_is_trauma_focused_cognitive_behavioral_therapy.pdfIn PDF document text
    • http://ximusutoj.pbworks.com/f/42450156477.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_off0000e391.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE391 5516 bytes
SHA-256: 1c5970bc60483569af15f0afc506d2204136cbd39746ef0d9b2763f1ceef35bc
font_01_sfnt_off0000f63d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF63D 12776 bytes
SHA-256: 306c20bbc3e6295e41bcfba18550ede1acb6622dee18997f7cdf85fcb697df8a