How severe is CVE-2020-29367?

CVE-2020-29367 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-29367 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-29367?

CVE-2020-29367 primarily affects Blosc C-blosc2. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-29367?

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-2020-29367 published?

CVE-2020-29367 was published on 2020-11-27 and last updated on 2026-06-17.

CVE-2020-29367

CVE-2020-29367 is a high-severity vulnerability in Blosc C-blosc2 with a CVSS 3.x base score of 7.8. 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Blosc C-blosc2
Published: 2020-11-27
Last modified: 2026-06-17

Description

blosc2.c in Blosc C-Blosc2 through 2.0.0.beta.5 has a heap-based buffer overflow when there is a lack of space to write compressed data.

Frequently asked questions

What is CVE-2020-29367?: blosc2.c in Blosc C-Blosc2 through 2.0.0.beta.5 has a heap-based buffer overflow when there is a lack of space to write compressed data.
How severe is CVE-2020-29367?: CVE-2020-29367 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-29367 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-29367?: CVE-2020-29367 primarily affects Blosc C-blosc2. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-29367?: 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-2020-29367 published?: CVE-2020-29367 was published on 2020-11-27 and last updated on 2026-06-17.

References

Affected products (9)

cpe:2.3:a:blosc:c-blosc2:2.0.0:alpha2:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:alpha3:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:alpha4:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:alpha5:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:beta1:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:beta2:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:beta3:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:beta4:*:*:*:*:*:*
cpe:2.3:a:blosc:c-blosc2:2.0.0:beta5:*:*:*:*:*:*

More vulnerabilities in Blosc C-blosc2

CVE-2023-37188 — High (CVSS 7.5): C-blosc2 before 2.9.3 was discovered to contain a NULL pointer dereference via the function zfp_rate_decompress at…
CVE-2023-37187 — High (CVSS 7.5): C-blosc2 before 2.9.3 was discovered to contain a NULL pointer dereference via the zfp/blosc2-zfp.c zfp_acc_decompress.…
CVE-2023-37186 — High (CVSS 7.5): C-blosc2 before 2.9.3 was discovered to contain a NULL pointer dereference in ndlz/ndlz8x8.c via a NULL pointer to…
CVE-2023-37185 — High (CVSS 7.5): C-blosc2 before 2.9.3 was discovered to contain a NULL pointer dereference via the function zfp_prec_decompress at…
CVE-2024-3204 — High (CVSS 7.3): A vulnerability has been found in c-blosc2 up to 2.13.2 and classified as critical. Affected by this vulnerability is…
CVE-2024-3203 — High (CVSS 7.3): A vulnerability, which was classified as critical, was found in c-blosc2 up to 2.13.2. Affected is the function…

All CVEs affecting Blosc C-blosc2 →

Other CWE-787 (Out-of-bounds Write) vulnerabilities

CVE-2026-42369 — Critical (CVSS 10.0): GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other…
CVE-2026-4746 — Critical (CVSS 10.0): Out-of-bounds Write vulnerability in timeplus-io proton (base/poco/Foundation/src‎ modules). This vulnerability is…
CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…

Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →