How severe is CVE-2026-25518?

CVE-2026-25518 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-25518 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-25518?

CVE-2026-25518 affects Cert-manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-25518?

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

Does CVE-2026-25518 have an EU (EUVD) identifier?

Yes. CVE-2026-25518 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5341.

When was CVE-2026-25518 published?

CVE-2026-25518 was published on 2026-02-04 and last updated on 2026-06-17.

CVE-2026-25518

CVE-2026-25518 is a medium-severity vulnerability in Cert-manager with a CVSS 3.x base score of 5.9. 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-129.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-5341
Weakness: CWE-129
Affected product: Cert-manager
Published: 2026-02-04
Last modified: 2026-06-17

Description

cert-manager adds certificates and certificate issuers as resource types in Kubernetes clusters, and simplifies the process of obtaining, renewing and using those certificates. In versions from 1.18.0 to before 1.18.5 and from 1.19.0 to before 1.19.3, the cert-manager-controller performs DNS lookups during ACME DNS-01 processing (for zone discovery and propagation self-checks). By default, these lookups use standard unencrypted DNS. An attacker who can intercept and modify DNS traffic from the cert-manager-controller pod can insert a crafted entry into cert-manager's DNS cache. Accessing this entry will trigger a panic, resulting in denial‑of‑service (DoS) of the cert-manager controller. The issue can also be exploited if the authoritative DNS server for the domain being validated is controlled by a malicious actor. This issue has been patched in versions 1.18.5 and 1.19.3.

Frequently asked questions

What is CVE-2026-25518?: cert-manager adds certificates and certificate issuers as resource types in Kubernetes clusters, and simplifies the process of obtaining, renewing and using those certificates. In versions from 1.18.0 to before 1.18.5 and from 1.19.0 to before 1.19.3, the cert-manager-controller performs DNS lookups during ACME DNS-01 processing (for zone discovery and propagation self-checks). By default, these lookups use standard unencrypted DNS. An attacker who can intercept and modify DNS traffic from the cert-manager-controller pod can insert a crafted entry into cert-manager's DNS cache. Accessing this entry will trigger a panic, resulting in denial‑of‑service (DoS) of the cert-manager controller. The issue can also be exploited if the authoritative DNS server for the domain being validated is controlled by a malicious actor. This issue has been patched in versions 1.18.5 and 1.19.3.
How severe is CVE-2026-25518?: CVE-2026-25518 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-25518 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-25518?: CVE-2026-25518 affects Cert-manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-25518?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-25518 have an EU (EUVD) identifier?: Yes. CVE-2026-25518 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5341.
When was CVE-2026-25518 published?: CVE-2026-25518 was published on 2026-02-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:cert-manager:cert-manager:*:*:*:*:*:*:*:*

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