How severe is CVE-2021-42075?

CVE-2021-42075 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-42075 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42075?

CVE-2021-42075 affects Barrier Project Barrier. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42075?

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-2021-42075 published?

CVE-2021-42075 was published on 2021-11-08 and last updated on 2026-06-17.

CVE-2021-42075

CVE-2021-42075 is a high-severity vulnerability in Barrier Project Barrier with a CVSS 3.x base score of 7.5. 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-772.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-772
Affected product: Barrier Project Barrier
Published: 2021-11-08
Last modified: 2026-06-17

Description

An issue was discovered in Barrier before 2.3.4. The barriers component (aka the server-side implementation of Barrier) does not correctly close file descriptors for established TCP connections. An unauthenticated remote attacker can thus cause file descriptor exhaustion in the server process, leading to denial of service.

Frequently asked questions

What is CVE-2021-42075?: An issue was discovered in Barrier before 2.3.4. The barriers component (aka the server-side implementation of Barrier) does not correctly close file descriptors for established TCP connections. An unauthenticated remote attacker can thus cause file descriptor exhaustion in the server process, leading to denial of service.
How severe is CVE-2021-42075?: CVE-2021-42075 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-42075 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42075?: CVE-2021-42075 affects Barrier Project Barrier. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42075?: 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-2021-42075 published?: CVE-2021-42075 was published on 2021-11-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:barrier_project:barrier:*:*:*:*:*:*:*:*

More vulnerabilities in Barrier Project Barrier

CVE-2021-42072 — High (CVSS 8.8): An issue was discovered in Barrier before 2.4.0. The barriers component (aka the server-side implementation of Barrier)…
CVE-2021-42073 — High (CVSS 8.2): An issue was discovered in Barrier before 2.4.0. An attacker can enter an active session state with the barriers…
CVE-2021-42076 — High (CVSS 7.5): An issue was discovered in Barrier before 2.3.4. An attacker can cause memory exhaustion in the barriers component (aka…
CVE-2021-42074 — High (CVSS 7.5): An issue was discovered in Barrier before 2.3.4. An unauthenticated attacker can cause a segmentation fault in the…

All CVEs affecting Barrier Project Barrier →

Other CWE-772 vulnerabilities

CVE-2020-12134 — Critical (CVSS 9.8): Nanometrics Centaur through 4.3.23 and TitanSMA through 4.2.20 mishandle access control for the syslog log.
CVE-2017-15032 — Critical (CVSS 9.8): ImageMagick version 7.0.7-2 contains a memory leak in ReadYCBCRImage in coders/ycbcr.c.
CVE-2017-14138 — Critical (CVSS 9.8): ImageMagick 7.0.6-5 has a memory leak vulnerability in ReadWEBPImage in coders/webp.c because memory is not freed in…
CVE-2017-11641 — Critical (CVSS 9.8): GraphicsMagick 1.3.26 has a Memory Leak in the PersistCache function in magick/pixel_cache.c during writing of Magick…
CVE-2020-14339 — High (CVSS 8.8): A flaw was found in libvirt, where it leaked a file descriptor for `/dev/mapper/control` into the QEMU process. This…
CVE-2018-19760 — High (CVSS 8.8): cfg_init in confuse.c in libConfuse 3.2.2 has a memory leak.

Browse all CWE-772 vulnerabilities →