temporalio/sqlparser deeply nested unary expressions can cause a fatal stack overflow during AST traversal

Description

temporalio/sqlparser accepts SQL containing deeply nested unary expressions and can return a correspondingly deep abstract syntax tree without enforcing an applicable nesting limit. The library's String and Walk operations recursively traverse that tree. An application that parses attacker-controlled SQL and later formats or walks the returned tree can encounter a runtime-fatal Go stack overflow that terminates the process; Go panic recovery cannot contain this condition. Temporal Server passes caller-controlled query input through the affected parser in archival, visibility, and worker-query paths. In affected validation paths, the Server recursively formats an invalid expression while constructing an error. In a supported authenticated deployment, a caller with namespace read permission can terminate the receiving Frontend or Matching process. The dynamically confirmed ListWorkers route additionally requires at least one retained worker heartbeat. Repeated requests can sustain a denial of service. The issue affects availability only; no confidentiality or integrity impact was identified.

Scores

EPSS (exploitation in 30 days)

0.67% · top 48% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.

Weakness

• CWE-674: Uncontrolled Recursion (opens in a new tab)All about CWE-674 and its CVEs

Affected products

• Temporal Technologies, Inc. · temporalio/sqlparser

  • affected 0.0.0-20141206041240-1aae9baceee8 – < 0.0.0-20260721183058-0466b6b405ac

• Temporal Technologies, Inc. · Temporal Server

  • unknown 0.0.0 – < 0.10.0
  • affected 0.10.0 – ≤ 1.29.7
  • affected 1.30.0 – < 1.30.7
  • affected 1.31.0 – < 1.31.3

What to do

Solution: Upgrade github.com/temporalio/sqlparser to v0.0.0-20260721183058-0466b6b405ac or later; v0.0.0-20260722001706-17d16cfe1da5 is the preferred upgrade. Temporal Server operators should upgrade to 1.30.7, 1.31.3, or 1.32.0, as appropriate for the deployed minor release line. The parser changes reject excessive nesting before recursive AST consumers receive an attacker-deep tree.

Workaround: Applications can impose a conservative query-size or nesting limit before parsing and avoid recursively formatting or walking parser-produced trees derived from untrusted input. Temporal Server 1.29 and 1.30 operators can disable ListWorkers when it is unused, disable unused archival reads, and restrict namespace read permission to trusted principals. Go panic recovery is not an effective mitigation for runtime-fatal stack overflow.

References (9)

• First affected sqlparser source revision (opens in a new tab)product
• sqlparser nested-expression fix pull request (opens in a new tab)patch
• First fixed sqlparser commit (opens in a new tab)patch
• Fixed release tag v0.1.0 (opens in a new tab)product
• Broader sqlparser AST-depth hardening (opens in a new tab)patch
• Temporal Server dependency update (opens in a new tab)patch
• Temporal Server 0.10.0 source-confirmed archival route (opens in a new tab)product
• Temporal Server 1.30.7 (opens in a new tab)release-notes
• Temporal Server 1.31.3 (opens in a new tab)release-notes

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-65651](https://trackcve.app/badge/CVE-2026-65651.svg)](https://trackcve.app/cve/CVE-2026-65651)

Record last updated 21 Sept 2026, 15:31 UTC.