How severe is CVE-2021-45468?

CVE-2021-45468 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-2021-45468 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45468?

CVE-2021-45468 affects Imperva Web Application Firewall. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-45468?

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-2021-45468 published?

CVE-2021-45468 was published on 2022-01-14 and last updated on 2026-06-17.

CVE-2021-45468

CVE-2021-45468 is a critical-severity vulnerability in Imperva Web Application Firewall with a CVSS 3.x base score of 9.8. 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-444.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Imperva Web Application Firewall
Published: 2022-01-14
Last modified: 2026-06-17

Description

Imperva Web Application Firewall (WAF) before 2021-12-23 allows remote unauthenticated attackers to use "Content-Encoding: gzip" to evade WAF security controls and send malicious HTTP POST requests to web servers behind the WAF.

Frequently asked questions

What is CVE-2021-45468?: Imperva Web Application Firewall (WAF) before 2021-12-23 allows remote unauthenticated attackers to use "Content-Encoding: gzip" to evade WAF security controls and send malicious HTTP POST requests to web servers behind the WAF.
How severe is CVE-2021-45468?: CVE-2021-45468 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-2021-45468 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45468?: CVE-2021-45468 affects Imperva Web Application Firewall. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-45468?: 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-2021-45468 published?: CVE-2021-45468 was published on 2022-01-14 and last updated on 2026-06-17.

References

https://bishopfox.com/blog/imperva-eliminates-critical-exposure

Affected products (1)

cpe:2.3:a:imperva:web_application_firewall:*:*:*:*:*:*:*:*

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