CVE-2021-43521
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog...
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.
- Record
CVE-2021-43521- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-787
- Updated
- 2026-11-02
CVE List No score
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.
- Record
CVE-2021-43521- Updated
- 2026-11-02
EUVDEUVD-2021-30450 No score
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.
- Record
EUVD-2021-30450- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-xhvg-qmw2-rr5r
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog...
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.
- Record
GHSA-xhvg-qmw2-rr5r- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.
- Record
CVE-2021-43521- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVOESA-2022-1652
zlog security update
zlog is a reliable, high-performance, thread safe, flexible, clear-model, pure C logging library.
Security Fix(es):
A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.(CVE-2021-43521)
- Record
OESA-2022-1652- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
zlogopenEuler:20.03-LTS-SP3 |
before 1.2.15-3.oe1 | 1.2.15-3.oe1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-43521 is a high vulnerability (CVSS 7.5) in Zlog Project Zlog, published April 8, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.28%, the 70th percentile. Fixed in zlog 1.2.15-3.oe1.