How severe is CVE-2026-26204?

CVE-2026-26204 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-26204 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-26204?

CVE-2026-26204 affects Wazuh. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-26204?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-26204 have an EU (EUVD) identifier?

Yes. CVE-2026-26204 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26259.

When was CVE-2026-26204 published?

CVE-2026-26204 was published on 2026-04-29 and last updated on 2026-06-17.

CVE-2026-26204

CVE-2026-26204 is a medium-severity vulnerability in Wazuh with a CVSS 3.x base score of 4.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-124.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-26259
Weakness: CWE-124
Affected product: Wazuh
Published: 2026-04-29
Last modified: 2026-06-17

Description

Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 1.0.0 to before version 4.14.4, a heap-based out-of-bounds WRITE occurs in GetAlertData, resulting in writing a NULL byte exactly 1 byte before the start of the buffer allocated by strdup. Due to unsigned integer underflow and pointer arithmetic wrapping, the write lands at offset -1 from the buffer, corrupting heap metadata. A malicious actor can potentially leverage this issue through a compromised agent to cause denial of service or heap corruption by injecting a specially crafted alert into the alerts log file monitored by wazuh-logcollector. This issue has been patched in version 4.14.4.

Frequently asked questions

What is CVE-2026-26204?: Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 1.0.0 to before version 4.14.4, a heap-based out-of-bounds WRITE occurs in GetAlertData, resulting in writing a NULL byte exactly 1 byte before the start of the buffer allocated by strdup. Due to unsigned integer underflow and pointer arithmetic wrapping, the write lands at offset -1 from the buffer, corrupting heap metadata. A malicious actor can potentially leverage this issue through a compromised agent to cause denial of service or heap corruption by injecting a specially crafted alert into the alerts log file monitored by wazuh-logcollector. This issue has been patched in version 4.14.4.
How severe is CVE-2026-26204?: CVE-2026-26204 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-26204 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-26204?: CVE-2026-26204 affects Wazuh. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-26204?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-26204 have an EU (EUVD) identifier?: Yes. CVE-2026-26204 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26259.
When was CVE-2026-26204 published?: CVE-2026-26204 was published on 2026-04-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:wazuh:wazuh:*:*:*:*:*:*:*:*

More vulnerabilities in Wazuh

CVE-2025-24016 — Critical (CVSS 9.9): Wazuh is a free and open source platform used for threat prevention, detection, and response. Starting in version 4.4.0…
CVE-2024-32038 — Critical (CVSS 9.8): Wazuh is a free and open source platform used for threat prevention, detection, and response. There is a buffer…
CVE-2021-44079 — Critical (CVSS 9.8): In the wazuh-slack active response script in Wazuh 4.2.x before 4.2.5, untrusted user agents are passed to a curl…
CVE-2026-25770 — Critical (CVSS 9.1): Wazuh is a free and open source platform used for threat prevention, detection, and response. Starting in version 3.9.0…
CVE-2026-25769 — Critical (CVSS 9.1): Wazuh is a free and open source platform used for threat prevention, detection, and response. Versions 4.0.0 through…
CVE-2026-30893 — Critical (CVSS 9.0): Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 4.4.0 to…

All CVEs affecting Wazuh →

Other CWE-124 vulnerabilities

CVE-2026-44631 — Critical (CVSS 9.8): Buffer Underwrite vulnerability in Apache HTTP Server on crafted regular expressions in the configuration. This issue…
CVE-2023-25610 — Critical (CVSS 9.8): A buffer underwrite ('buffer underflow') vulnerability in the administrative interface of Fortinet FortiOS version…
CVE-2025-27440 — High (CVSS 8.5): Heap overflow in some Zoom Workplace Apps may allow an authenticated user to conduct an escalation of privilege via…
CVE-2025-27439 — High (CVSS 8.5): Buffer underflow in some Zoom Workplace Apps may allow an authenticated user to conduct an escalation of privilege via…
CVE-2026-34253 — High (CVSS 8.2): A buffer underflow vulnerability has been identified in the ogg123 utility from the vorbis-tools 1.4.3 package in…
CVE-2026-0966 — High (CVSS 8.2): A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing…

Browse all CWE-124 vulnerabilities →