{"answers":{"affected":"3 open source packages ship an affected version, including mcp-atlassian. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-77272 in the wild and no public exploit code.","fix":"Upgrade mcp-atlassian to 0.22.0 or later.","what":"CVE-2026-77272 is a medium-severity cross-site scripting vulnerability in sooperset mcp-atlassian, published on 22 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-77272 and fix it if it is affected.\n\nWhat it is: CVE-2026-77272 is a medium-severity cross-site scripting vulnerability in sooperset mcp-atlassian, published on 22 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-77272 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- mcp-atlassian (PyPI): affected all versions; fixed in 0.22.0\n- mcp-atlassian (PyPI): affected all versions; fixed in 0.22.0\n- mcp-atlassian (PyPI): affected all versions; fixed in 0.22.0\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-77272/ (Markdown: https://insights.sbomify.com/CVE-2026-77272/index.md)","id":"CVE-2026-77272","markdown":"https://insights.sbomify.com/CVE-2026-77272/index.md","name":"CVE-2026-77272","record":{"aliases":["GHSA-g2r2-3j32-j27x","PYSEC-2026-4093"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"MCP Atlassian server","requires_auth":"none","summary":"Attackers can inject scripts into the OAuth callback page, executing code in the victim's browser during the authentication flow.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"mcp_atlassian","vendor":"mcp-atlassian"}],"cvss":{"score":5.4,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the OAuth error query parameter is passed to CallbackHandler._send_response in oauth_setup.py and interpolated into an HTML page without escaping. A crafted authorization callback can inject markup or script that executes in the browser of a user completing the OAuth flow. This issue is fixed in version 0.22.0.","ecosystems":["PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"MCP Atlassian: Reflected XSS in OAuth Setup Callback Handler","id":"CVE-2026-77272","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":3,"n_references":4,"next":{"headline":"MCP Atlassian: SSRF Protection Bypass","id":"CVE-2026-77274"},"packages":[{"ecosystem":"PyPI","fixed":["0.22.0"],"introduced":["0"],"last_affected":[],"package":"mcp-atlassian","purl":null,"source":"GHSA-g2r2-3j32-j27x"},{"ecosystem":"PyPI","fixed":["0.22.0"],"introduced":["0"],"last_affected":[],"package":"mcp-atlassian","purl":"pkg:pypi/mcp-atlassian","source":"GHSA-g2r2-3j32-j27x"},{"ecosystem":"PyPI","fixed":["0.22.0"],"introduced":["0"],"last_affected":[],"package":"mcp-atlassian","purl":"pkg:pypi/mcp-atlassian","source":"PYSEC-2026-4093"}],"prev":{"headline":"MCP Atlassian: Incomplete path traversal fix allows intra-CWD module overwrite and RCE (bypass of CVE-2026-27825)","id":"CVE-2026-77271"},"products":["mcp-atlassian"],"published":"2026-09-22","related":[{"cvss_score":10,"headline":"[mcp-atlassian] Authentication bypass in HTTP transport: AtlassianOpaqueTokenVerifier accepts any non-empty token","id":"CVE-2026-77244","kev_date_added":null,"published":"2026-09-22"},{"cvss_score":9.1,"headline":"MCP Atlassian: Unauthenticated HTTP MCP requests can use globally configured Jira and Confluence credentials","id":"CVE-2026-77254","kev_date_added":null,"published":"2026-09-22"},{"cvss_score":9.1,"headline":"MCP Atlassian has an arbitrary file write leading to arbitrary code execution via unconstrained download_path in confluence_download_attachment","id":"CVE-2026-27825","kev_date_added":null,"published":"2026-03-10"},{"cvss_score":8.8,"headline":"MCP Atlassian: ENABLED_TOOLS / Toolset authorization bypass","id":"CVE-2026-77243","kev_date_added":null,"published":"2026-09-22"},{"cvss_score":8.8,"headline":"MCP Atlassian: SSRF Protection Bypass","id":"CVE-2026-77274","kev_date_added":null,"published":"2026-09-22"},{"cvss_score":8.6,"headline":"MCP Atlassian: Unauthenticated arbitrary local file read via upload_attachment file_path, chained with missing auth on streamable-http transport","id":"CVE-2026-77248","kev_date_added":null,"published":"2026-09-22"},{"cvss_score":8.6,"headline":"MCP Atlassian: Arbitrary File Read \u0026 Exfiltration (Confused Deputy) in JIRA update_issue","id":"CVE-2026-77255","kev_date_added":null,"published":"2026-09-22"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-09-23","vendors":["sooperset"]},"summary":"Attackers can inject scripts into the OAuth callback page, executing code in the victim's browser during the authentication flow.","url":"https://insights.sbomify.com/CVE-2026-77272/"}