How severe is CVE-2021-23053?

CVE-2021-23053 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-23053 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23053?

CVE-2021-23053 primarily affects F5 Big-ip Advanced Web Application Firewall. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-23053?

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

When was CVE-2021-23053 published?

CVE-2021-23053 was published on 2021-09-14 and last updated on 2026-06-17.

CVE-2021-23053

CVE-2021-23053 is a medium-severity vulnerability in F5 Big-ip Advanced Web Application Firewall with a CVSS 3.x base score of 5.3. 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-770.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 4.3
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: F5 Big-ip Advanced Web Application Firewall
Published: 2021-09-14
Last modified: 2026-06-17

Description

On version 15.1.x before 15.1.3, 14.1.x before 14.1.3.1, and 13.1.x before 13.1.3.6, when the brute force protection feature of BIG-IP Advanced WAF or BIG-IP ASM is enabled on a virtual server and the virtual server is under brute force attack, the MySQL database may run out of disk space due to lack of row limit on undisclosed tables in the MYSQL database. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Frequently asked questions

What is CVE-2021-23053?: On version 15.1.x before 15.1.3, 14.1.x before 14.1.3.1, and 13.1.x before 13.1.3.6, when the brute force protection feature of BIG-IP Advanced WAF or BIG-IP ASM is enabled on a virtual server and the virtual server is under brute force attack, the MySQL database may run out of disk space due to lack of row limit on undisclosed tables in the MYSQL database. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
How severe is CVE-2021-23053?: CVE-2021-23053 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-23053 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23053?: CVE-2021-23053 primarily affects F5 Big-ip Advanced Web Application Firewall. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-23053?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-23053 published?: CVE-2021-23053 was published on 2021-09-14 and last updated on 2026-06-17.

References

https://support.f5.com/csp/article/K36942191

Affected products (2)

cpe:2.3:a:f5:big-ip_advanced_web_application_firewall:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*

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