CVE-2021-20202
Temporary Directory Hijacking Vulnerability in Keycloak
A flaw was found in keycloak. Directories can be created prior to the Java process creating them in the temporary directory, but with wider user permissions, allowing the attacker to have access to the contents that keycloak stores in this directory. The highest threat from this vulnerability is to data confidentiality and integrity.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- Low
Exploit likelihood
What each source reports
NVD Score used
A flaw was found in keycloak. Directories can be created prior to the Java process creating them in the temporary directory, but with wider user permissions, allowing the attacker to have access to the contents that keycloak stores in this directory. The highest threat from this vulnerability is to data confidentiality and integrity.
- Record
CVE-2021-20202- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L - CVSS 2.0
- 4.6 Medium
AV:L/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-377
- Updated
- 2026-11-02
CVE List No score
A flaw was found in keycloak. Directories can be created prior to the Java process creating them in the temporary directory, but with wider user permissions, allowing the attacker to have access to the contents that keycloak stores in this directory. The highest threat from this vulnerability is to data confidentiality and integrity.
- Record
CVE-2021-20202- Weakness
- CWE-377
- Updated
- 2026-11-02
EUVDEUVD-2022-1350 No score
A flaw was found in keycloak. Directories can be created prior to the Java process creating them in the temporary directory, but with wider user permissions, allowing the attacker to have access to the contents that keycloak stores in this directory. The highest threat from this vulnerability is to data confidentiality and integrity.
- Record
EUVD-2022-1350- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-6xp6-fmc8-pmmr
Temporary Directory Hijacking Vulnerability in Keycloak
A flaw was found in keycloak. Directories can be created prior to the Java process creating them in the temporary directory, but with wider user permissions, allowing the attacker to have access to the contents that keycloak stores in this directory. The highest threat from this vulnerability is to data confidentiality and integrity.
- Record
GHSA-6xp6-fmc8-pmmr- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L - Weakness
- CWE-377
- Updated
- 2026-11-02
OSV
A flaw was found in keycloak. Directories can be created prior to the Java process creating them in the temporary directory, but with wider user permissions, allowing the attacker to have access to the contents that keycloak stores in this directory. The highest threat from this vulnerability is to data confidentiality and integrity.
- Record
CVE-2021-20202- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L - Updated
- 2026-11-02
OSVGHSA-6xp6-fmc8-pmmr
Temporary Directory Hijacking Vulnerability in Keycloak
A flaw was found in keycloak. Directories can be created prior to the Java process creating them in the temporary directory, but with wider user permissions, allowing the attacker to have access to the contents that keycloak stores in this directory. The highest threat from this vulnerability is to data confidentiality and integrity.
- Record
GHSA-6xp6-fmc8-pmmr- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L - Weakness
- CWE-377
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
org.keycloak:keycloak-coreMaven |
before 13.0.0 | 13.0.0 |
org.keycloak:keycloak-coreMaven |
before 13.0.0, plus listed versions 1.0-alpha-11.0-alpha-1-120620131.0-alpha-21.0-alpha-31.0-alpha-4 Show 45 moreShow less1.0-beta-11.0-beta-1-201505211.0-beta-1-201505231.0-beta-21.0-beta-31.0-beta-41.0-final1.0-rc-11.0-rc-21.0.1.Final1.0.2.Final1.0.3.Final1.0.4.Final1.0.5.Final1.1.0.Beta11.1.0.Beta21.1.0.Final1.1.1.Final1.2.0.Beta11.2.0.CR11.2.0.Final1.3.0.Final1.3.1.Final1.4.0.Final1.5.0-Final1.5.0.Final1.5.1.Final1.6.0.Final1.6.1.Final1.7.0.CR11.7.0.Final1.8.0.Alpha11.8.0.CR11.8.0.CR21.8.0.CR31.8.0.Final1.8.1.Final1.9.0.CR11.9.0.Final1.9.1.Final1.9.2.Final1.9.3.Final1.9.4.Final1.9.5.Final1.9.7.Final |
13.0.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20202 is a high vulnerability (CVSS 7.3) in Keycloak, published May 12, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.30%, the 22nd percentile. Fixed in org.keycloak:keycloak-core 13.0.0.
References
Left out here: 72 versions. The JSON record has them.