How severe is CVE-2021-31923?

CVE-2021-31923 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 low, and availability none.

Is CVE-2021-31923 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31923?

CVE-2021-31923 affects Pingidentity Pingaccess. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-31923?

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

When was CVE-2021-31923 published?

CVE-2021-31923 was published on 2021-09-24 and last updated on 2026-06-17.

CVE-2021-31923

CVE-2021-31923 is a medium-severity vulnerability in Pingidentity Pingaccess 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-444.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Pingidentity Pingaccess
Published: 2021-09-24
Last modified: 2026-06-17

Description

Ping Identity PingAccess before 5.3.3 allows HTTP request smuggling via header manipulation.

Frequently asked questions

What is CVE-2021-31923?: Ping Identity PingAccess before 5.3.3 allows HTTP request smuggling via header manipulation.
How severe is CVE-2021-31923?: CVE-2021-31923 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 low, and availability none.
Is CVE-2021-31923 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31923?: CVE-2021-31923 affects Pingidentity Pingaccess. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-31923?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-31923 published?: CVE-2021-31923 was published on 2021-09-24 and last updated on 2026-06-17.

References

https://docs.pingidentity.com/bundle/pingaccess-53/page/wco1629833104567.html

Affected products (1)

cpe:2.3:a:pingidentity:pingaccess:*:*:*:*:*:*:*:*

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