How severe is CVE-2020-11521?

CVE-2020-11521 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-11521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11521?

CVE-2020-11521 primarily affects Freerdp. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-11521?

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

When was CVE-2020-11521 published?

CVE-2020-11521 was published on 2020-05-15 and last updated on 2026-06-17.

CVE-2020-11521

CVE-2020-11521 is a medium-severity vulnerability in Freerdp with a CVSS 3.x base score of 6.6. 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-125.

Key facts

Severity: Medium (CVSS 3.x base score 6.6)
CVSS v2: 6.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Freerdp
Published: 2020-05-15
Last modified: 2026-06-17

Description

libfreerdp/codec/planar.c in FreeRDP version > 1.0 through 2.0.0-rc4 has an Out-of-bounds Write.

Frequently asked questions

What is CVE-2020-11521?: libfreerdp/codec/planar.c in FreeRDP version > 1.0 through 2.0.0-rc4 has an Out-of-bounds Write.
How severe is CVE-2020-11521?: CVE-2020-11521 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-11521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11521?: CVE-2020-11521 primarily affects Freerdp. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-11521?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-11521 published?: CVE-2020-11521 was published on 2020-05-15 and last updated on 2026-06-17.

References

Affected products (13)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*
cpe:2.3:a:freerdp:freerdp:2.0.0:-:*:*:*:*:*:*
cpe:2.3:a:freerdp:freerdp:2.0.0:rc0:*:*:*:*:*:*
cpe:2.3:a:freerdp:freerdp:2.0.0:rc1:*:*:*:*:*:*
cpe:2.3:a:freerdp:freerdp:2.0.0:rc2:*:*:*:*:*:*
cpe:2.3:a:freerdp:freerdp:2.0.0:rc3:*:*:*:*:*:*
cpe:2.3:a:freerdp:freerdp:2.0.0:rc4:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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Other CWE-125 (Out-of-bounds Read) vulnerabilities

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