CVE-2026-76340: In Splunk Enterprise 10.4 versions below 10.4.2, an unauthenticated user could cause Splunk Enterprise to relo

Routine

MEDIUM 5.3REMOTEUPGRADE

CVE-2026-76340 is a medium-severity flaw (CVSS 5.3) affecting splunk. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

In Splunk Enterprise 10.4 versions below 10.4.2, an unauthenticated user could cause Splunk Enterprise to reload token-signing keys through the Representational State Transfer (REST) API. The vulnerability does not affect Splunk Enterprise versions below 10.4. The vulnerability is possible because the REST API does not require authentication or the change_authentication capability for the token-key reload action. For more information see Define r

Why this priority

Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.4% (top 69%)
CISA exploited list	No
Weakness	CWE-862
Published	2026-08-19
Last modified	2026-08-26

Publisher (CNA): Cisco Systems, Inc. · Vendor: splunk

Last updated 2026-08-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-08-19 22:17 UTCPublished CVE record published
2026-08-26 16:16 UTCUpdated Record last modified

splunk splunk UPGRADE

Affected: >= 10.4.0 and < 10.4.2

Fixed in: 10.4.2

Safe to downgrade to: a release before 10.4.0

1. Check installed version

apt-cache policy splunk || rpm -q splunk || splunk --version

2. UPGRADE to 10.4.2 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade splunk

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade splunk

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 10.4.0 (Debian / Ubuntu)

apt-cache madison splunk sudo apt install splunk=<VERSION_BEFORE_10.4.0> sudo apt-mark hold splunk

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list splunk sudo dnf downgrade splunk-<VERSION_BEFORE_10.4.0> sudo dnf versionlock add splunk

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-76340?

splunk: upgrade to 10.4.2. Exact commands for each OS are on this page.

Is CVE-2026-76340 being exploited?

CVE-2026-76340 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-76340 affect?

CVE-2026-76340 affects splunk. Severity is medium (CVSS 5.3). In Splunk Enterprise 10.4 versions below 10.4.2, an unauthenticated user could cause Splunk Enterprise to reload token-signing keys through the Representational State Transfer (REST) API. The vulnerability does not affect Splunk Enterprise

How urgent is CVE-2026-76340?

Priority 31/100. Remotely exploitable, no login, no user action

Software pages

Splunk vulnerabilities

Related CVEs

CVE-2026-20202 MEDIUM 6.6 UPGRADE UPGRADE In Splunk Enterprise versions below 10.2.2, 10.0.5, 9.4.10, and 9.3.11, and Splunk Cloud Platform versions bel
CVE-2026-20204 HIGH 7.1 UPGRADE UPGRADE In Splunk Enterprise versions below 10.2.1, 10.0.5, 9.4.10, and 9.3.11, and Splunk Cloud Platform versions bel
CVE-2026-20203 MEDIUM 4.3 UPGRADE UPGRADE In Splunk Enterprise versions below 10.2.2, 10.0.5, 9.4.10, and 9.3.11, and Splunk Cloud Platform versions bel
CVE-2026-76257 MEDIUM 6.5 UPGRADE UPGRADE In Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.14, and Splunk Secure Gateway versions bel
CVE-2026-76258 MEDIUM 6.5 UPGRADE UPGRADE In Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.14, and Splunk Secure Gateway versions bel

References

← Back to latest CVEs