How severe is CVE-2021-29108?

CVE-2021-29108 has a CVSS 3.x base score of 8.8, 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 high, and availability high.

Is CVE-2021-29108 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29108?

CVE-2021-29108 affects Esri Portal For Arcgis. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29108?

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-2021-29108 published?

CVE-2021-29108 was published on 2021-10-01 and last updated on 2026-06-17.

CVE-2021-29108

CVE-2021-29108 is a high-severity vulnerability in Esri Portal For Arcgis with a CVSS 3.x base score of 8.8. 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-347.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Esri Portal For Arcgis
Published: 2021-10-01
Last modified: 2026-06-17

Description

There is an privilege escalation vulnerability in organization-specific logins in Esri Portal for ArcGIS versions 10.9 and below that may allow a remote, authenticated attacker who is able to intercept and modify a SAML assertion to impersonate another account (XML Signature Wrapping Attack). In addition patching, Esri also strongly recommends as best practice for SAML assertions to be signed and encrypted.

Frequently asked questions

What is CVE-2021-29108?: There is an privilege escalation vulnerability in organization-specific logins in Esri Portal for ArcGIS versions 10.9 and below that may allow a remote, authenticated attacker who is able to intercept and modify a SAML assertion to impersonate another account (XML Signature Wrapping Attack). In addition patching, Esri also strongly recommends as best practice for SAML assertions to be signed and encrypted.
How severe is CVE-2021-29108?: CVE-2021-29108 has a CVSS 3.x base score of 8.8, 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 high, and availability high.
Is CVE-2021-29108 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29108?: CVE-2021-29108 affects Esri Portal For Arcgis. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29108?: 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-2021-29108 published?: CVE-2021-29108 was published on 2021-10-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:esri:portal_for_arcgis:*:*:*:*:*:*:*:*

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