How severe is CVE-2021-21669?

CVE-2021-21669 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-21669 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 26% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21669?

CVE-2021-21669 affects Jenkins Generic Webhook Trigger. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-21669?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-21669 published?

CVE-2021-21669 was published on 2021-06-18 and last updated on 2026-06-17.

CVE-2021-21669

CVE-2021-21669 is a critical-severity vulnerability in Jenkins Generic Webhook Trigger with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 26% places it in the 98th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 26% (98th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Jenkins Generic Webhook Trigger
Published: 2021-06-18
Last modified: 2026-06-17

Description

Jenkins Generic Webhook Trigger Plugin 1.72 and earlier does not configure its XML parser to prevent XML external entity (XXE) attacks.

Frequently asked questions

What is CVE-2021-21669?: Jenkins Generic Webhook Trigger Plugin 1.72 and earlier does not configure its XML parser to prevent XML external entity (XXE) attacks.
How severe is CVE-2021-21669?: CVE-2021-21669 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-21669 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 26% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21669?: CVE-2021-21669 affects Jenkins Generic Webhook Trigger. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21669?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-21669 published?: CVE-2021-21669 was published on 2021-06-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:jenkins:generic_webhook_trigger:*:*:*:*:*:jenkins:*:*

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