How severe is CVE-2021-27772?

CVE-2021-27772 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability low.

Is CVE-2021-27772 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27772?

CVE-2021-27772 affects Hcltech Sametime. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27772?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-27772 published?

CVE-2021-27772 was published on 2022-05-12 and last updated on 2026-06-17.

CVE-2021-27772

CVE-2021-27772 is a high-severity vulnerability in Hcltech Sametime with a CVSS 3.x base score of 7.1. 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-285.

Key facts

Severity: High (CVSS 3.x base score 7.1)
CVSS v2: 4.0
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-285
Affected product: Hcltech Sametime
Published: 2022-05-12
Last modified: 2026-06-17

Description

Users are able to read group conversations without actively taking part in them. Next to one to one conversations, users are able to start group conversations with multiple users. It was found possible to obtain the contents of these group conversations without being part of it. This could lead to information leakage where confidential information discussed in private groups is read by other users without the users knowledge.

Frequently asked questions

What is CVE-2021-27772?: Users are able to read group conversations without actively taking part in them. Next to one to one conversations, users are able to start group conversations with multiple users. It was found possible to obtain the contents of these group conversations without being part of it. This could lead to information leakage where confidential information discussed in private groups is read by other users without the users knowledge.
How severe is CVE-2021-27772?: CVE-2021-27772 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability low.
Is CVE-2021-27772 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27772?: CVE-2021-27772 affects Hcltech Sametime. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27772?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-27772 published?: CVE-2021-27772 was published on 2022-05-12 and last updated on 2026-06-17.

References

https://support.hcltechsw.com/csm?id=kb_article&sysparm_article=KB0097430

Affected products (1)

cpe:2.3:a:hcltech:sametime:11.6:*:*:*:*:*:*:*

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