{"id":"CVE-2026-129484","kind":"vulnerability","aliases":["CVE-2026-129484"],"related":[],"title":"Kroki: reflected XSS via SVG color options runs script in victims' browsers","description":"Kroki before 0.36.0 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts via unvalidated svg-color-dark-scheme and svg-color-light-scheme options. Attackers can craft a GET /goat/svg URL whose option value closes the SVG style element, executing JavaScript in the Kroki origin when victims open it.","summary":"Kroki, a diagram rendering service, fails to validate the svg-color-dark-scheme and svg-color-light-scheme options on its GET /goat/svg endpoint. An attacker can craft a link whose option value closes the SVG style element, so JavaScript runs in the Kroki origin when a victim opens it.","severity":"medium","cvss":6.1,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["diagrams","kroki","other","self-hosted"],"not_affected_if":["fixed-version","not-internet-exposed"],"how_to_check":"- Check the running Kroki version: `kroki --version` or the image tag in your deployment, and compare it with `0.36.0`.\n- Look for any reverse proxy or gateway logs showing requests to `/goat/svg` with `svg-color-dark-scheme` or `svg-color-light-scheme` parameters containing `</style>`.","fix":"- Kroki: move to `0.36.0` or later.","status":"open","published_at":"2026-11-15T16:16:56+00:00","first_seen_at":"2026-11-15T16:35:38+00:00","triaged_at":"2026-11-15T16:37:16+00:00","updated_at":"2026-11-15T16:37:16+00:00","category":"other","confidence":0.6,"triage":{"at":"2026-11-15T16:37:16Z","model":"claude-haiku-5-5","output":{"fix":"- Kroki: move to `0.36.0` or later.","reach":"internet","title":"Kroki: reflected XSS via SVG color options runs script in victims' browsers","impact":"medium","summary":"Kroki, a diagram rendering service, fails to validate the svg-color-dark-scheme and svg-color-light-scheme options on its GET /goat/svg endpoint. An attacker can craft a link whose option value closes the SVG style element, so JavaScript runs in the Kroki origin when a victim opens it.","audience":"businesses","category":"other","nicknames":[],"who_cares":["kroki","self-hosted","diagrams"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"script runs in the Kroki origin in a victim's browser","analyst_note":"","how_to_check":"- Check the running Kroki version: `kroki --version` or the image tag in your deployment, and compare it with `0.36.0`.\n- Look for any reverse proxy or gateway logs showing requests to `/goat/svg` with `svg-color-dark-scheme` or `svg-color-light-scheme` parameters containing `</style>`.","plain_action":"","product_name":"","needs_analyst":false,"not_affected_if":["fixed-version","not-internet-exposed"],"who_is_affected":"Any team running a self-hosted Kroki instance older than 0.36.0 that is reachable by users or other systems. The exploit needs a crafted link opened by a victim, so instances not exposed to a browser-facing network and running the fixed version can skip it. Managed or fully private deployments are less exposed.","user_interaction":"yes","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.00076,"input_tokens":4656,"output_tokens":589,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-129484':15A,18A '-2026':14A,17A '/goat/svg':49B,113C '0.36.0':78C 'allow':88C 'attack':52B,90C,108C 'browser':12A 'close':60B,118C 'color':6A,36B,42B,98C,104C 'contain':79C 'craft':54B,110C 'cross':83C 'cross-sit':82C 'cve':13A,16A 'dark':37B,99C 'diagram':19B,27B 'element':64B,122C 'endpoint':50B 'execut':123C 'fail':30B 'get':48B,112C 'host':24B 'inject':92C 'javascript':66B,124C 'kroki':1A,20B,25B,70B,76C,127C 'light':43B,105C 'link':56B 'open':75B,131C 'option':7A,45B,58B,107C,116C 'origin':71B,128C 'reflect':2A,81C 'render':28B 'run':8A,67B 'scheme':38B,44B,100C,106C 'script':9A,85C,93C 'self':23B 'self-host':22B 'servic':29B 'site':84C 'style':63B,121C 'svg':5A,35B,41B,62B,97C,103C,120C 'svg-color-dark-schem':34B,96C 'svg-color-light-schem':40B,102C 'unauthent':89C 'unvalid':95C 'url':114C 'valid':32B 'valu':59B,117C 'via':4A,94C 'victim':11A,74B,130C 'vulner':86C 'whose':57B,115C 'xss':3A","nicknames":[],"mitigations":[],"who_affected":"Any team running a self-hosted Kroki instance older than 0.36.0 that is reachable by users or other systems. The exploit needs a crafted link opened by a victim, so instances not exposed to a browser-facing network and running the fixed version can skip it. Managed or fully private deployments are less exposed.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["diagrams","kroki","medium","other","selfhosted"],"campaign_type":null,"search_a":"'-129484':15A,18A '-2026':14A,17A 'browser':12A 'color':6A 'cve':13A,16A 'kroki':1A 'option':7A 'reflect':2A 'run':8A 'script':9A 'svg':5A 'via':4A 'victim':11A 'xss':3A","search_b":"'/goat/svg':49B 'attack':52B 'close':60B 'color':36B,42B 'craft':54B 'dark':37B 'diagram':19B,27B 'element':64B 'endpoint':50B 'fail':30B 'get':48B 'host':24B 'javascript':66B 'kroki':20B,25B,70B 'light':43B 'link':56B 'open':75B 'option':45B,58B 'origin':71B 'render':28B 'run':67B 'scheme':38B,44B 'self':23B 'self-host':22B 'servic':29B 'style':63B 'svg':35B,41B,62B 'svg-color-dark-schem':34B 'svg-color-light-schem':40B 'valid':32B 'valu':59B 'victim':74B 'whose':57B","search_c":"'/goat/svg':113C '0.36.0':78C 'allow':88C 'attack':90C,108C 'close':118C 'color':98C,104C 'contain':79C 'craft':110C 'cross':83C 'cross-sit':82C 'dark':99C 'element':122C 'execut':123C 'get':112C 'inject':92C 'javascript':124C 'kroki':76C,127C 'light':105C 'open':131C 'option':107C,116C 'origin':128C 'reflect':81C 'scheme':100C,106C 'script':85C,93C 'site':84C 'style':121C 'svg':97C,103C,120C 'svg-color-dark-schem':96C 'svg-color-light-schem':102C 'unauthent':89C 'unvalid':95C 'url':114C 'valu':117C 'via':94C 'victim':130C 'vulner':86C 'whose':115C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-09T17:56:16+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"disclosure@vulncheck.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-129484","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-129484","severity":null,"published_at":"2026-11-15T16:16:56+00:00","modified_at":"2026-11-15T16:16:56+00:00","first_seen_at":"2026-11-15T16:35:38+00:00","fetched_at":"2026-11-15T16:35:38+00:00","note":null}],"documents":[{"id":164388,"url":"https://github.com/yuzutech/kroki/commit/a0a1435cc38eb7b258c555a883b7687424ad6784","title":"Patch: github.com","kind":"other","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Patch: github.com"},{"id":157578,"url":"https://github.com/yuzutech/kroki/releases/tag/v0.36.0","title":"Release notes: github.com","kind":"release","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Release notes: github.com"},{"id":164390,"url":"https://github.com/yuzutech/kroki/security/advisories/GHSA-xp94-px2v-f7f2","title":"Vendor advisory: github.com","kind":"vendor","source":"nvd","publisher":"vendor","text":null,"published_at":"2026-11-09T17:56:16+00:00","relation":"advisory","confidence":null,"note":"Vendor advisory: github.com"},{"id":164391,"url":"https://www.vulncheck.com/advisories/kroki-before-0.36.0-reflected-xss-via-goat-svg-color-scheme-options","title":"Third-party advisory: www.vulncheck.com","kind":"advisory","source":"nvd","publisher":"research","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":"Third-party advisory: www.vulncheck.com"}],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}