⚠ Reference material — not professional advice. Test in staging, back up first, verify against your specific version. Use your own judgment for your environment.
● Medium · CVSS 6.8

How to Fix CVE-2026-25727: Stack Buffer Overflow in time

Other vulnerabilities in the same area that are worth patching alongside this one:

*By Sai Kiran Pandrala*

⚡ At a glance
SeverityCVSS 6.8 - Medium
Actively exploited?Not currently listed in CISA KEV
Affected>= 0.3.6, < 0.3.47
Fixed inSee vendor advisory
Type (CWE)CWE-121: Stack-based Buffer Overflow

What is CVE-2026-25727?

CVE-2026-25727 is a stack-based buffer overflow in time. A remote attacker can send a crafted message that overflows a fixed-size stack buffer, corrupting the return address and, on un-mitigated builds, achieving code execution. Vendor description: time provides date and time handling in Rust. From 0.3.6 to before 0.3.47, when user-provided input is provided to any type that parses with the RFC 2822 format, a denial of service attack via stack exhaustion is possible.

Why this CVE matters

Stack-based buffer overflows in network-reachable services have driven some of the highest-impact incidents of the past two years. Modern compiler protections raise the bar, but real-world exploits for unpatched appliances continue to appear quickly after disclosure.

For deployments of time that have been exposed to the public internet during the disclosure window, the operating assumption should be that scanning has already happened. Even where exploitation has not been publicly observed, scanning for the vulnerable fingerprint is cheap and routine. Patching closes the door; log review and credential rotation close out the rest of the response.

Am I affected?

You are affected if your installation matches any of these version ranges:

Check your installed version against the list above. If you cannot determine the version, treat the system as affected and follow the upgrade path below.

Open time's About dialog or run the vendor-documented version-check command. Compare the result against the affected ranges in the advisory.

How to fix CVE-2026-25727

  1. Read the vendor advisory in full: https://github.com/time-rs/time/security/advisories/GHSA-r6v5-fh4h-64xc
  2. Upgrade time to the patched build listed in the vendor advisory.
  3. Back up the configuration (and database, where applicable) before upgrading.
  4. Apply the patch in a maintenance window. For HA pairs, upgrade the standby node first, fail over, then upgrade the former primary.
  5. Restart the affected service so the patched binary loads, then verify the new version (see verification section).

Patched-version commands

Vendor advisory: https://github.com/time-rs/time/security/advisories/GHSA-r6v5-fh4h-64xc

Affected: time: >= 0.3.6, < 0.3.47

Patched in: <patched-version-from-advisory>


# Vendor advisory: https://github.com/time-rs/time/security/advisories/GHSA-r6v5-fh4h-64xc

# npm / Yarn / pnpm.
npm install time@<patched-version-from-advisory>
npm ls time

# Python / pip.
python -m pip install --upgrade "time>=<patched-version-from-advisory>"
python -m pip show time

# Container image.
docker pull <your-registry>/time:<patched-version-from-advisory>
docker stop time && docker rm time
docker run -d --name time <your-registry>/time:<patched-version-from-advisory>


# Vendor advisory: https://github.com/time-rs/time/security/advisories/GHSA-r6v5-fh4h-64xc
# Same flow from a Windows admin workstation.
npm install time@<patched-version-from-advisory>
docker pull <your-registry>/time:<patched-version-from-advisory>

Verify the fix landed


# Vendor advisory: https://github.com/time-rs/time/security/advisories/GHSA-r6v5-fh4h-64xc
# Post-patch verification (replace <service> with the real service unit).
journalctl -u <service> --since "10 minutes ago"
dmesg --since "10 minutes ago"

# Re-scan with your vulnerability scanner (Nessus, Qualys, Tenable, OpenVAS).
# It should no longer flag CVE-2026-25727 on the patched target.

If you cannot patch immediately

Block network reachability to the vulnerable service from untrusted networks and apply the patched build. Memory-corruption bugs cannot be reliably mitigated at the network layer; the patch is the fix.

How to verify the fix worked

If your installation was internet-reachable during the disclosure window, treat log review as part of the remediation rather than an optional follow-up. Look for repeated service restarts, crash logs from the affected daemon, and core files generated around the time of any anomalous traffic. A memory-corruption flaw used for exploitation often leaves a trail of failed attempts before the successful one.

Frequently asked questions

Is CVE-2026-25727 being exploited in the wild?

Public exploitation has not been confirmed by CISA at the time of writing. Treat the patch as time-sensitive anyway; reports often lag actual abuse.

Will a WAF or IDS rule fully mitigate CVE-2026-25727?

No. Network-layer filters can reduce noise and slow opportunistic scanners, but they will not stop a determined attacker. The vendor patch is the only durable fix.

How long should I plan for the upgrade?

Typical vendor-documented upgrade windows for time run from a few minutes to under an hour depending on cluster size. Test in a staging environment first and follow the vendor's documented HA upgrade order.

References

*This guide was assembled from the official vendor advisory, the NVD record, and the CISA KEV catalog entry on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*