How severe is CVE-2021-20253?

CVE-2021-20253 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20253 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20253?

CVE-2021-20253 affects Redhat Ansible Tower. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20253?

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

When was CVE-2021-20253 published?

CVE-2021-20253 was published on 2021-03-09 and last updated on 2026-06-17.

CVE-2021-20253

CVE-2021-20253 is a medium-severity vulnerability in Redhat Ansible Tower with a CVSS 3.x base score of 6.7. 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-552.

Key facts

Severity: Medium (CVSS 3.x base score 6.7)
CVSS v2: 3.5
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-552
Affected product: Redhat Ansible Tower
Published: 2021-03-09
Last modified: 2026-06-17

Description

A flaw was found in ansible-tower. The default installation is vulnerable to Job Isolation escape allowing an attacker to elevate the privilege from a low privileged user to the awx user from outside the isolated environment. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Frequently asked questions

What is CVE-2021-20253?: A flaw was found in ansible-tower. The default installation is vulnerable to Job Isolation escape allowing an attacker to elevate the privilege from a low privileged user to the awx user from outside the isolated environment. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
How severe is CVE-2021-20253?: CVE-2021-20253 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20253 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20253?: CVE-2021-20253 affects Redhat Ansible Tower. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20253?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20253 published?: CVE-2021-20253 was published on 2021-03-09 and last updated on 2026-06-17.

References

https://bugzilla.redhat.com/show_bug.cgi?id=1928847

Affected products (1)

cpe:2.3:a:redhat:ansible_tower:*:*:*:*:*:*:*:*

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