Use After Free in Opengauss-Server Opengauss-Server-7.0.0-Rc1
CVE-2026-14178
openGauss 在处理带 NLS 参数的 to_timestamp 调用时，to_timestamp_with_fmt_nls() 会将 nls_fmt_str 保存到 u_sess->parser_cxt.nls_fmt_str。在 seqscan + sort 执行路径下，该字符串原本被分配在 SeqScan 的表达式上下文中；当 SeqScan 完成后，该内存上下文会被 reset，但后续结果输出阶段 timestamp_out() 仍会通过 CheckNlsFormat() 访问 u_sess->parser_cxt.nls_fmt_str，导致访问已释放内存。攻击者在具备数据库 SQL 执行权限的情况下，可构造特定 to_timestamp(..., ..., nlsparam) 查询触发 heap-use-after-free。在 ASan/Memcheck 环境下表现为数据库服务退出；在实际运行环境中可能造成后端进程异常退出，影响数据库服务可用性，形成拒绝服务风险。该问题在openGauss-server-7.0.0-RC1版本和openGauss-server-7.0.0-RC2版本存在，目前已在openGauss-server-7.0.0-RC3版本修复。由于 openGauss-server-7.0.0-RC1版本和openGauss-server-7.0.0-RC2均为创新版本，不会发布针对性补丁包，涉及版本升级至 openGauss-server-7.0.0-RC3或更新版本即可。
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (28.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 28.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Opengauss-Server Opengauss-Server-7.0.0-Rc1 — versions openGauss-server-7.0.0-RC1
- Opengauss-Server Opengauss-Server-7.0.0-Rc2 — versions openGauss-server-7.0.0-RC2
- Opengauss-Server Opengauss-Server-7.0.0-Rc3 — versions openGauss-server-7.0.0-RC3
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-14178?
- CVE-2026-14178 is a medium-severity vulnerability in Opengauss-Server Opengauss-Server-7.0.0-Rc1, classified under Use After Free. CVSS score: 5.9/10. Published 2026-06-30.
- How severe is CVE-2026-14178?
- Medium severity. CVSS v3 base score is 5.9 out of 10.