Jenkins Security Advisory 2021-05-25

Affects plugin: Filesystem Trigger Affects plugin: Markdown Formatter Affects plugin: Nuget Affects plugin: URLTrigger

CSIRTS triage

What: Multiple plugins are affected by security vulnerabilities.
Who is affected: Deployments of the affected plugins in Jenkins.
Urgency: Remediation is necessary as vulnerabilities could be exploited, though exploitation status is currently unknown.
Action: Update the affected plugins to their latest versions.

AI-assisted analysis generated from the source advisory — verify against the original.

⚡ Watch Jenkins

Get an email when a new Jenkins advisory drops — max one per day, one-click unsubscribe.

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Moderate exploitation riskCVE-2021-216571.6% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 73% of all EPSS-scored CVEs.
Moderate exploitation riskCVE-2021-216581.5% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 73% of all EPSS-scored CVEs.
Exploitation likely imminentCVE-2021-21659EPSS puts this in the most-targeted tier (66.8% 30-day exploitation probability). Prioritize alongside KEV items. Riskier than 99.3% of all EPSS-scored CVEs.
Moderate exploitation riskCVE-2021-216601.1% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 62% of all EPSS-scored CVEs.

CVE	CSIRTS overview	External
CVE-2021-21657	coverage & exploitation status	NVD · CVE.org
CVE-2021-21658	coverage & exploitation status	NVD · CVE.org
CVE-2021-21659	coverage & exploitation status	NVD · CVE.org
CVE-2021-21660	coverage & exploitation status	NVD · CVE.org