Malicious PDF — malware analysis report

Static analysis result for SHA-256 287b0673deab8e88…

MALICIOUS

PDF

72.5 KB Created: 2021-04-11 20:16:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: f781538bb19c2f813ffb852ebb54d9df SHA-1: cc1ecddafb32dfcd07f76a0f2668810c4e9f5943 SHA-256: 287b0673deab8e88950c68375241165145bf7b3783ffbd10787484529fa0a4a8
126 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, and contains numerous embedded URLs, many of which are hosted on disposable domains. One prominent URL, 'https://pelibibifir.ru/strik?utm_term=wordpress+social+login+rest+api', is flagged as an external URI. The PDF structure and the presence of multiple links suggest a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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 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://pelibifir.ru/strik?utm_term=wordpress+social+login+rest+api PDF link annotation
    • http://fusozurima.22web.org/literary_theory_and_criticism_an_introduction.pdfIn PDF document text
    • https://cdn.sqhk.co/rolileduvof/vhjSthg/zombie_road_racing_mod_apk_free_download.pdfIn PDF document text
    • https://cdn.sqhk.co/xawodoze/vghjge4/84844380974.pdfIn PDF document text
    • https://cdn.sqhk.co/xumupojamax/hhauWgf/nelaxupewadose.pdfIn PDF document text
    • http://drenajkrasnodar.ru/kuzavarilanokedugogabuz6jn9l.pdfIn PDF document text
    • http://retoxen.mypressonline.com/understanding_psychology_kasschau.pdfIn PDF document text
    • http://bibivire.mygamesonline.org/jerry_kuhnhausen_1911_shop_manual_vol_2.pdfIn PDF document text
    • http://idealicaitalia-official.site/what_should_i_write_in_my_personal_statement_for_medical_schoolzzwu9.pdfIn PDF document text
    • http://makedctl.site/progressive_dynamics_power_converter_wiring_diagramm386c.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/sobaketemu/who_invented_homework_for_students.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7d441a41-363f-4f4a-8962-578088286f7b/naronolomisotobe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d57d31ad-b99d-4507-9fa9-ec6254142423/true_colors_assessment_results.pdfIn PDF document text
    • http://sizesetuxuw.rf.gd/quimica_inorganica_peter_atkins_descargar.pdfIn PDF document text
    • https://s3.amazonaws.com/tezude/army_pistol_training_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/wovigebi/pifij.pdfIn PDF document text
    • http://jasunusemoki.onlinewebshop.net/zapixapodenopezizasiwona.pdfIn PDF document text
    • http://rotodeperev.rf.gd/25535747703.pdfIn PDF document text
    • https://s3.amazonaws.com/nojemi/is_dect_6.0_secure.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/64990d01-cbf4-45ed-a499-77d46e150c6c/38852233614.pdfIn PDF document text
    • https://s3.amazonaws.com/rizezobabub/rap_music_beats.pdfIn PDF document text
    • http://tivogowajap.epizy.com/information_security_classification_framework_2013.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb67561c-69db-4bea-a4f6-b7bbf8419dfa/dbt_residential_treatment_near_me.pdfIn PDF document text
    • http://sopexalibip.onlinewebshop.net/jepedepetesezunuw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77922137-c6bd-403a-8b92-ed114b92af08/67132125104.pdfIn PDF document text
    • http://lusiromipu.epizy.com/virewuberorekeniwobuva.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
    • https://public-api.wordpress.com/rest/v1.1/meIn 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_off0000de48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE48 5256 bytes
SHA-256: 864c09f1effb93471f1f934fd96bd6dde352c0984dc813adb3a09b48846df2d4
font_01_sfnt_off0000f047.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF047 10196 bytes
SHA-256: 74aa0c0d06ffb41e9c0f2fe3d55748f4c438e8aed41c164c218d8494c165b4bb