{"id":"CVE-2021-26828","kind":"vulnerability","aliases":["CVE-2021-26828"],"related":[],"title":"OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows remote authenticated users to upload and…","description":"OpenPLC ScadaBR contains an unrestricted upload of file with dangerous type vulnerability that allows remote authenticated users to upload and execute arbitrary JSP files via view_edit.shtm.\n\nCISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","summary":"OpenPLC ScadaBR, an industrial control system SCADA web interface, lets a logged-in user upload a JSP file through view_edit.shtm and run it on the server. An attacker who has any valid account gets code execution on the host, and CISA lists it as actively exploited.","severity":"high","cvss":8.8,"epss":null,"exploited":true,"exploited_at":"2025-12-03T00:00:00+00:00","products":[{"name":"OpenPLC ScadaBR","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"scadabr","fixed":[],"affected":"<= 0.9.1","ecosystem":"vendor"},{"name":"scadabr","fixed":[],"affected":"<= 1.12.4","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","industrial-control","infrastructure","openplc","scadabr","self-hosted"],"not_affected_if":["no-scadabr-installed"],"how_to_check":null,"fix":"Apply the vendor mitigation per CISA guidance; the sources do not name a fixed version. If no mitigation exists, discontinue use of the product.","status":"open","published_at":"2021-06-11T12:15:12+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T20:44:15+00:00","updated_at":"2026-10-23T23:44:51+00:00","category":"infrastructure","confidence":0.7,"triage":{"at":"2026-10-23T20:44:15Z","model":"claude-haiku-5-5","output":{"fix":"Apply the vendor mitigation per CISA guidance; the sources do not name a fixed version. If no mitigation exists, discontinue use of the product.","reach":"network","summary":"OpenPLC ScadaBR, an industrial control system SCADA web interface, lets a logged-in user upload a JSP file through view_edit.shtm and run it on the server. An attacker who has any valid account gets code execution on the host, and CISA lists it as actively exploited.","category":"infrastructure","who_cares":["scadabr","openplc","industrial-control","self-hosted"],"confidence":0.7,"needs_auth":"yes","worst_case":"Attacker runs arbitrary JSP code on the server, reading secrets and controlling the plant.","analyst_note":"Find the vendor advisory or fixed ScadaBR version and a detection step (e.g. look for unexpected .jsp files in the webapp directory) from the CISA KEV entry or NVD.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["no-scadabr-installed"],"user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000459,"input_tokens":2570,"output_tokens":403,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-01':123C '-2021':19A,22A '-26828':20A,23A '0.9.1':4A '1.12.4':9A '22':122C 'account':71B 'action':113C 'activ':83B 'allow':12A,98C 'appli':114C 'applic':120C 'arbitrari':106C 'attack':66B 'authent':14A,100C 'bod':121C 'cisa':79B,111C 'cloud':126C 'code':73B 'contain':87C 'control':31B,42B 'cve':18A,21A 'danger':94C 'discontinu':129C 'execut':74B,105C 'exploit':28B,84B 'file':56B,92C,108C 'follow':119C 'get':72B 'guidanc':124C 'host':37B,77B 'industri':30B,41B 'industrial-control':29B 'infrastructur':32B 'instruct':118C 'interfac':46B 'jsp':55B,107C 'let':47B 'linux':6A 'list':80B 'log':50B 'logged-in':49B 'mitig':115C,135C 'openplc':1A,24A,33B,38B,85C 'per':116C 'product':133C 'remot':13A,99C 'requir':112C 'run':60B 'scada':44B 'scadabr':2A,25A,26A,27A,34B,39B,86C 'self':36B 'self-host':35B 'server':64B 'servic':127C 'system':43B 'type':95C 'unavail':137C 'unrestrict':89C 'upload':17A,53B,90C,103C 'use':130C 'user':15A,52B,101C 'valid':70B 'vendor':117C 'via':109C 'view_edit.shtm':58B,110C 'vulner':96C 'web':45B 'window':11A","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2021-06-11T12:15:12+00:00","kev":{"dateAdded":"2025-12-03","dueDate":"2025-12-24","requiredAction":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2021-26828","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-26828","severity":null,"published_at":"2025-12-03T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-25T14:39:38+00:00","note":null},{"source":"nvd","external_id":"CVE-2021-26828","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-26828","severity":null,"published_at":"2021-06-11T12:15:12+00:00","modified_at":"2026-06-17T03:43:49+00:00","first_seen_at":"2026-10-23T23:44:51+00:00","fetched_at":"2026-10-23T23:44:51+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}