How severe is CVE-2023-20255?

CVE-2023-20255 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-2023-20255 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-20255?

CVE-2023-20255 affects Cisco Meeting Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-20255?

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

When was CVE-2023-20255 published?

CVE-2023-20255 was published on 2023-11-01 and last updated on 2026-06-17.

CVE-2023-20255

CVE-2023-20255 is a medium-severity vulnerability in Cisco Meeting Server 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Meeting Server
Published: 2023-11-01
Last modified: 2026-06-17

Description

A vulnerability in an API of the Web Bridge feature of Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to insufficient validation of HTTP requests. An attacker could exploit this vulnerability by sending crafted HTTP packets to an affected device. A successful exploit could allow the attacker to cause a partial availability condition, which could cause ongoing video calls to be dropped due to the invalid packets reaching the Web Bridge.

Frequently asked questions

What is CVE-2023-20255?: A vulnerability in an API of the Web Bridge feature of Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to insufficient validation of HTTP requests. An attacker could exploit this vulnerability by sending crafted HTTP packets to an affected device. A successful exploit could allow the attacker to cause a partial availability condition, which could cause ongoing video calls to be dropped due to the invalid packets reaching the Web Bridge.
How severe is CVE-2023-20255?: CVE-2023-20255 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-2023-20255 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-20255?: CVE-2023-20255 affects Cisco Meeting Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-20255?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-20255 published?: CVE-2023-20255 was published on 2023-11-01 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cms-segfault-G6ES4Ve8

Affected products (1)

cpe:2.3:a:cisco:meeting_server:*:*:*:*:*:*:*:*

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