Malicious PDF — malware analysis report

Static analysis result for SHA-256 1af51d63f5ee6786…

MALICIOUS

PDF

77.0 KB Created: 2021-06-08 22:04:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 9f1b7146a146313d6e9ca1a5b356da54 SHA-1: ee27292a8ebe9d02a0b17e867972e4a7d1896a4d SHA-256: 1af51d63f5ee6786b4872bcce811dd5d140d316cfb681d17d724bf3a950c651e
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are hosted on disposable domains, indicating a link farm or SEO spam campaign. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://philabc.ru/pbw?utm_term=least+common+denominator+worksheet+5th+grade PDF link annotation
    • https://wobapuzufisuro.weebly.com/uploads/1/3/4/0/134042344/wuvifexalivut.pdfIn PDF document text
    • https://xekotetumisas.weebly.com/uploads/1/3/5/2/135295861/48ba57e1.pdfIn PDF document text
    • https://jurexufibemoso.weebly.com/uploads/1/3/4/3/134310147/4099404.pdfIn PDF document text
    • https://kebakikuvoti.weebly.com/uploads/1/3/7/5/137513313/buvagonirifopod.pdfIn PDF document text
    • https://vizazoxo.weebly.com/uploads/1/3/4/6/134600102/vakilumudifa.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/c0ce06e6-6ad2-4c69-a8aa-248bc665b8ae/77892111638.pdfIn PDF document text
    • http://pamijokoja.pbworks.com/w/file/fetch/144776358/62026050463.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/656255d3-0a76-479c-b973-943b096b0f64/visual_basic_2010_express_free_download_full_version_with_crack.pdfIn PDF document text
    • http://gurilotav.pbworks.com/w/file/fetch/144828507/19393008067.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/887c4ba3-c732-4a2e-9f09-d03a66170e3c/rca_phone_model_25425re1-a_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af9c6bba-f57f-416b-8502-28300d9462e0/tv_sony_trinitron_mati_standby.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0fa3bee0-7c57-4dcd-9b72-e07d27084dc0/26357603788.pdfIn PDF document text
    • http://saxonax.pbworks.com/f/how_to_set_the_time_on_a_gourmet_classic_double_oven.pdfIn PDF document text
    • http://xujefix.pbworks.com/f/8_week_olympic_triathlon_training_plan_beginner.pdfIn PDF document text
    • http://vazesuna.pbworks.com/w/file/fetch/144500403/welding_technology_fundamentals_answer_key.pdfIn PDF document text
    • http://mumubib.pbworks.com/w/file/fetch/144413340/ejercicios_resueltos_de_gases_ideales_fisicoquimica.pdfIn PDF document text
    • http://tikomegeto.pbworks.com/w/file/fetch/144888051/subway_surfers_mod_version_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/41ddeef7-2597-4370-9cdc-a4ab195f6273/dagimebitodedox.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/65fcc53d-cac7-45d1-871a-2731739b5df2/wivizagisefilum.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/715be73c-ae13-4195-b921-7895f6e4892b/56772104023.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/93ac35ba-2fc4-4e47-a681-31a36757268a/adjusting_carb_on_poulan_p3314.pdfIn PDF document text
    • http://sinorodolu.pbworks.com/w/file/fetch/144605502/what_is_the_average_customer_acquisition_cost.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_off0000ef3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3E 5540 bytes
SHA-256: 9bd1f936d473ef704eb9b8ca1190fe9df5f11f6e3800fa57f4c00e5c4e28f6e2
font_01_sfnt_off00010204.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10204 10524 bytes
SHA-256: 84ae3a235d731c3558d4e7c2fbf0043f885aff02e0edbdd0a39f94a4637329b2