Oxia affected by server crash via race condition in session heartbeat handling

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-40943: 0.20% estimated exploitation activity in the next 30 days; percentile 10.15 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A race condition between session heartbeat processing and session closure can cause the server to panic with send on closed channel. The heartbeat() method uses a blocking channel send while holding a mutex, and under specific timing with concurrent close() calls, this can lead to either a deadlock (channel buffer full) or a panic (send on closed channel after TOCTOU gap in KeepAlive). Impact A remote client can trigger a server crash by sending rapid KeepAlive requests while a session is expiring or being closed. This is a denial-of-service vulnerability that crashes the entire data server process. All versions are affected. Details In oxiad/dataserver/controller/lead/session.go, the heartbeat() method performs a blocking s.heartbeatCh <- true send. If the channel buffer is full (size 1), this blocks while holding the session mutex, preventing close() from acquiring the lock to close the channel — a deadlock. Additionally, in sessionmanager.go, KeepAlive() releases the…

Published by the source

14 Apr 2026, 23:15 UTC

Last modified by the source

24 Apr 2026, 20:39 UTC

Source last checked

26 Oct 2026, 15:19 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-5gqc-qhrj-9xw8

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# Patch Next advisory brief: CVE-2026-40943

Advisory: Oxia affected by server crash via race condition in session heartbeat handling
IDs: CVE-2026-40943, GHSA-5gqc-qhrj-9xw8
Record: https://patchnext.com/advisories/cve-2026-40943 (revision 1, source checked 26 Oct 2026, 15:19 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/oxia-db/oxia 0.16.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/oxia-db/oxia: affected <= 0.16.1; fixed in 0.16.2

## Suggested inspection (read-only)
- Go github.com/oxia-db/oxia: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/oxia-db/oxia.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-5gqc-qhrj-9xw8 (GitHub-reviewed advisory GHSA-5gqc-qhrj-9xw8 lists affected ranges: Go github.com/oxia-db/oxia >=0 <=0.16.1)

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