ZDF
Sign inSign up

Vulnerabilities

Security fix · CVE-2025-8396

Insufficiently specific bounds checking on authorization header could lead to denial of service in the Temporal server on all platforms due to excessive memory allocation.This issu

Published Sep 15, 2025 · catalog updated Sep 15, 2025 · Temporal OSS Server

Last checked Oct 29, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2025-8396. EPSS is 0.39%. Act only if a listed version of Temporal OSS Server is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Medium6.9
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.39%
Remediation
Version ranges on file
Affected products
vendor Temporal OSS Server 1.27.0 <1.27.3

Insufficiently specific bounds checking on authorization header could lead to denial of service in the Temporal server on all platforms due to excessive memory allocation.This issue affects all platforms and versions of OSS Server prior to 1.26.3, 1.27.3, and 1.28.1 (i.e., fixed in 1.26.3, 1.27.3, and 1.28.1 and later). Temporal Cloud services are not impacted.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • vendor Temporal OSS Server 1.27.0 <1.27.31.27.0 <1.27.3

How to fix CVE-2025-8396

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2025-8396. EPSS is 0.39%. Act only if a listed version of Temporal OSS Server is installed.

Which versions are affected?

Compare what you have installed with Temporal OSS Server 1.27.0 <1.27.3 1.27.0 <1.27.3. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 0.39%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Sep 15, 2025 · EUVD

    Detected

    Insufficiently specific bounds checking on authorization header could lead to denial of service in the Temporal server on all platforms due to excessive memory allocation.This issue affects all platforms and versions of OSS Server prior to 1.26.3, 1.27.3, and 1.28.1 (i.e., fixed in 1.26.3, 1.27.3, and 1.28.1 and later). Temporal Cloud services are not impacted.

  2. Sep 15, 2025 · EUVD

    Updated

    Insufficiently specific bounds checking on authorization header could lead to denial of service in the Temporal server on all platforms due to excessive memory allocation.This issue affects all platforms and versions of OSS Server prior to 1.26.3, 1.27.3, and 1.28.1 (i.e., fixed in 1.26.3, 1.27.3, and 1.28.1 and later). Temporal Cloud services are not impacted.

Sources

  • CVE.orgVulnerability recordCVE-2025-8396

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-8396

    30-day exploitation probability 0.39%

    first.org
  • EUVDVulnerability recordEUVD-2025-29200

    Insufficiently specific bounds checking on authorization header could lead to denial of service in the Temporal server on all platforms due to excessive memory allocation.This issue affects all platforms and versions of OSS Server prior to 1.26.3, 1.27.3, and 1.28.1 (i.e., fixed

    euvd.enisa.europa.eu

References

Freshness

Last verified in this catalog Oct 29, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • EUVDOct 23, 2026
  • FIRST EPSSOct 23, 2026
  • CVE.orgOct 22, 2026