How severe is CVE-2021-20786?

CVE-2021-20786 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-20786 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20786?

CVE-2021-20786 primarily affects Groupsession. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20786?

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

When was CVE-2021-20786 published?

CVE-2021-20786 was published on 2021-07-30 and last updated on 2026-06-17.

CVE-2021-20786

CVE-2021-20786 is a medium-severity vulnerability in Groupsession with a CVSS 3.x base score of 4.3. 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-352.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-352
Affected product: Groupsession
Published: 2021-07-30
Last modified: 2026-06-17

Description

Cross-site request forgery (CSRF) vulnerability in GroupSession (GroupSession Free edition from ver2.2.0 to the version prior to ver5.1.0, GroupSession byCloud from ver3.0.3 to the version prior to ver5.1.0, and GroupSession ZION from ver3.0.3 to the version prior to ver5.1.0) allows a remote attacker to hijack the authentication of administrators via a specially crafted URL.

Frequently asked questions

What is CVE-2021-20786?: Cross-site request forgery (CSRF) vulnerability in GroupSession (GroupSession Free edition from ver2.2.0 to the version prior to ver5.1.0, GroupSession byCloud from ver3.0.3 to the version prior to ver5.1.0, and GroupSession ZION from ver3.0.3 to the version prior to ver5.1.0) allows a remote attacker to hijack the authentication of administrators via a specially crafted URL.
How severe is CVE-2021-20786?: CVE-2021-20786 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-20786 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20786?: CVE-2021-20786 primarily affects Groupsession. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20786?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20786 published?: CVE-2021-20786 was published on 2021-07-30 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:groupsession:groupsession:*:*:*:*:free:*:*:*
cpe:2.3:a:groupsession:groupsession_bycloud:*:*:*:*:*:*:*:*
cpe:2.3:a:groupsession:groupsession_zion:*:*:*:*:*:*:*:*

More vulnerabilities in Groupsession

CVE-2021-20874 — High (CVSS 7.5): Incorrect permission assignment for critical resource vulnerability in GroupSession Free edition ver5.1.1 and earlier,…
CVE-2021-20876 — Medium (CVSS 6.8): Path traversal vulnerability in GroupSession Free edition ver5.1.1 and earlier, GroupSession byCloud ver5.1.1 and…
CVE-2017-2165 — Medium (CVSS 6.5): GroupSession versions 4.6.4 and earlier allows remote authenticated attackers to bypass access restrictions to obtain…
CVE-2025-65120 — Medium (CVSS 6.1): Reflected cross-site scripting vulnerability exists in GroupSession Free edition prior to ver5.7.1, GroupSession…
CVE-2025-57883 — Medium (CVSS 6.1): Reflected cross-site scripting vulnerability exists in GroupSession Free edition prior to ver5.3.0, GroupSession…
CVE-2025-54407 — Medium (CVSS 6.1): Stored cross-site scripting vulnerability exists in GroupSession Free edition prior to ver5.3.0, GroupSession byCloud…

All CVEs affecting Groupsession →

Other CWE-352 (Cross-Site Request Forgery (CSRF)) vulnerabilities

CVE-2025-32642 — Critical (CVSS 10.0): Cross-Site Request Forgery (CSRF) vulnerability in appsbd Vite Coupon vite-coupon allows Remote Code Inclusion.This…
CVE-2025-23922 — Critical (CVSS 10.0): Cross-Site Request Forgery (CSRF) vulnerability in Harsh iSpring Embedder embed-ispring allows Upload a Web Shell to a…
CVE-2017-5145 — Critical (CVSS 10.0): An issue was discovered in Carlo Gavazzi VMU-C EM prior to firmware Version A11_U05, and VMU-C PV prior to firmware…
CVE-2019-25729 — Critical (CVSS 9.8): PDF Signer 3.0 contains a server-side template injection vulnerability that allows unauthenticated attackers to execute…
CVE-2025-48340 — Critical (CVSS 9.8): Cross-Site Request Forgery (CSRF) vulnerability in Danny Vink User Profile Meta Manager user-profile-meta allows…
CVE-2025-2907 — Critical (CVSS 9.8): The Order Delivery Date WordPress plugin before 12.3.1 does not have authorization and CSRF checks when importing…

Browse all CWE-352 (Cross-Site Request Forgery (CSRF)) vulnerabilities →