How severe is CVE-2026-53440?

CVE-2026-53440 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-53440 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-53440?

CVE-2026-53440 primarily affects Jenkins. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-53440?

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

Does CVE-2026-53440 have an EU (EUVD) identifier?

Yes. CVE-2026-53440 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-36024.

When was CVE-2026-53440 published?

CVE-2026-53440 was published on 2026-06-10 and last updated on 2026-06-17.

CVE-2026-53440

CVE-2026-53440 is a medium-severity vulnerability in Jenkins with a CVSS 3.x base score of 4.3. 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-601.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-36024
Weakness: CWE-601
Affected product: Jenkins
Published: 2026-06-10
Last modified: 2026-06-17

Description

Jenkins 2.567 and earlier, LTS 2.555.2 and earlier does not ensure that the "from" parameter in the "Delegate to servlet container" security realm is safe to redirect to after login, allowing attackers to perform phishing attacks by redirecting users to an attacker-controlled domain.

Frequently asked questions

What is CVE-2026-53440?: Jenkins 2.567 and earlier, LTS 2.555.2 and earlier does not ensure that the "from" parameter in the "Delegate to servlet container" security realm is safe to redirect to after login, allowing attackers to perform phishing attacks by redirecting users to an attacker-controlled domain.
How severe is CVE-2026-53440?: CVE-2026-53440 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-53440 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-53440?: CVE-2026-53440 primarily affects Jenkins. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-53440?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-53440 have an EU (EUVD) identifier?: Yes. CVE-2026-53440 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-36024.
When was CVE-2026-53440 published?: CVE-2026-53440 was published on 2026-06-10 and last updated on 2026-06-17.

References

https://www.jenkins.io/security/advisory/2026-06-10/#SECURITY-3721

Affected products (2)

cpe:2.3:a:jenkins:jenkins:*:*:*:*:lts:*:*:*
cpe:2.3:a:jenkins:jenkins:*:*:*:*:-:*:*:*

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Other CWE-601 (Open Redirect) vulnerabilities

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CVE-2020-36912 — Critical (CVSS 9.8): Plexus anblick Digital Signage Management 3.1.13 contains an open redirect vulnerability in the 'PantallaLogin' script…
CVE-2025-43526 — Critical (CVSS 9.8): This issue was addressed with improved URL validation. This issue is fixed in Safari 26.2, macOS Tahoe 26.2. On a Mac…
CVE-2025-55031 — Critical (CVSS 9.8): Malicious pages could use Firefox for iOS to pass FIDO: links to the OS and trigger the hybrid passkey transport. An…
CVE-2024-22891 — Critical (CVSS 9.8): Nteract v.0.28.0 was discovered to contain a remote code execution (RCE) vulnerability via the Markdown link.

Browse all CWE-601 (Open Redirect) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

125.212.235.194 (ipv4-addr)
220.95.208.142 (ipv4-addr)