Raw vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LSummary
CVE-2026-20797 is a medium-severity Out-of-bounds Write (CWE-787) vulnerability in Copeland Xweb 300D Pro Firmware. Its CVSS base score is 4.3 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 47% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-20797 is a stack-based buffer overflow vulnerability (CWE-787) present in an API route of XWEB Pro version 1.12.1 and prior. Published on 2026-02-27, the flaw enables stack corruption and program termination. It carries a CVSS v3.1 base score of 4.3 (AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L).
Unauthenticated attackers (PR:N) with adjacent network access (AV:A) can exploit this low-complexity (AC:L) vulnerability without user interaction (UI:N). Successful exploitation results in stack corruption, causing termination of the XWEB Pro program and a low-impact denial-of-service condition (A:L), with no effects on confidentiality or integrity.
CISA's ICS Advisory ICSA-26-057-10 details the vulnerability and mitigation steps at https://www.cisa.gov/news-events/ics-advisories/icsa-26-057-10, with the corresponding CSAF document available at https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-057-10.json. Copeland provides a system software update for remediation at https://webapps.copeland.com/Dixell/Pages/SystemSoftwareUpdate.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-8972
Vulnerability Data
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.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 2 hardening rules · 2 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation (including fuzzing and bounds checks) finds out-of-bounds write flaws before deployment.
Input validation directly stops untrusted data from exceeding stack buffer bounds.
Memory-protection mechanisms limit the ability to execute injected code after a stack overflow.
Requiring documented secure-development standards and tools can mandate bounds-checked coding practices that avoid the weakness.
Secure-engineering principles include bounds-checked coding and safe buffer handling that avoid introducing the flaw.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.
Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.
Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development and acceptance can detect and prevent out-of-bounds write defects.
Secure development life cycle mandates practices that prevent out-of-bounds writes.
Application security requirements can specify bounds-checking and safe memory handling.
Secure architecture and engineering principles reduce the likelihood of buffer overflows.
Secure coding directly addresses out-of-bounds writes through language choice and coding standards.
Change management can enforce review gates that catch unsafe memory operations before deployment.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. prevents CWE-121
Oracle Linux 9 (1 rule)
- V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-121