What’s Vulnerable › Vulnerabilities

CVE-2026-20797: Copeland XWEB and XWEB Pro Stack-based Buffer Overflow

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-02-27 · updated 2026-06-17
• Weakness: CWE-787

Description

A stack based buffer overflow exists in an API route of XWEB Pro version 1.12.1 and prior, enabling unauthenticated attackers to cause stack corruption and a termination of the program.

Affected products

• Copeland Xweb 300D Pro Firmware: through 1.12.1
• Copeland Xweb 500B Pro Firmware: through 1.12.1
• Copeland Xweb 500D Pro Firmware: through 1.12.1

References

• https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-057-10.json
• https://webapps.copeland.com/Dixell/Pages/SystemSoftwareUpdate
• https://www.cisa.gov/news-events/ics-advisories/icsa-26-057-10

Get alerted when CVE-2026-20797 or the next vulnerability affects your stack