How severe is CVE-2026-23534?

CVE-2026-23534 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-23534 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-23534?

CVE-2026-23534 affects Freerdp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-23534?

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

Does CVE-2026-23534 have an EU (EUVD) identifier?

Yes. CVE-2026-23534 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3314.

When was CVE-2026-23534 published?

CVE-2026-23534 was published on 2026-01-19 and last updated on 2026-06-30.

CVE-2026-23534

CVE-2026-23534 is a critical-severity vulnerability in Freerdp with a CVSS 3.x base score of 9.8. 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-122.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 7.7
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-3314
Weakness: CWE-122
Affected product: Freerdp
Published: 2026-01-19
Last modified: 2026-06-30

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the ClearCodec bands decode path when crafted band coordinates allow writes past the end of the destination surface buffer. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.

Frequently asked questions

What is CVE-2026-23534?: FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the ClearCodec bands decode path when crafted band coordinates allow writes past the end of the destination surface buffer. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.
How severe is CVE-2026-23534?: CVE-2026-23534 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-23534 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-23534?: CVE-2026-23534 affects Freerdp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-23534?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-23534 have an EU (EUVD) identifier?: Yes. CVE-2026-23534 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3314.
When was CVE-2026-23534 published?: CVE-2026-23534 was published on 2026-01-19 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

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