CVE-2021-45931
CVE-2021-45931 is a medium-severity vulnerability in Harfbuzz Project Harfbuzz with a CVSS 3.x base score of 6.5. 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-787.
Key facts
- Severity: Medium (CVSS 3.x base score 6.5)
- CVSS v2: 4.3
- EPSS exploit prediction: 2% (76th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Harfbuzz Project Harfbuzz
- Published:
- Last modified:
Description
HarfBuzz 2.9.0 has an out-of-bounds write in hb_bit_set_invertible_t::set (called from hb_sparseset_t<hb_bit_set_invertible_t>::set and hb_set_copy).
Frequently asked questions
- What is CVE-2021-45931?
- HarfBuzz 2.9.0 has an out-of-bounds write in hb_bit_set_invertible_t::set (called from hb_sparseset_t<hb_bit_set_invertible_t>::set and hb_set_copy).
- How severe is CVE-2021-45931?
- CVE-2021-45931 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-45931 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-45931?
- CVE-2021-45931 primarily affects Harfbuzz Project Harfbuzz. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-45931?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-45931 published?
- CVE-2021-45931 was published on 2022-01-01 and last updated on 2026-06-17.
References
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=37425
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/harfbuzz/OSV-2021-1159.yaml
- https://github.com/harfbuzz/harfbuzz/commit/d3e09bf4654fe5478b6dbf2b26ebab6271317d81
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4EAIZKL4O67FN2CWJYHYKZEMNYWNWO3D/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5A7TCR2MY46YK3NHQZB3SLESUH354IEA/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DI6247WOAKB46CZZ6SCDSJVWWCW3GMZH/
- https://security.gentoo.org/glsa/202209-11
Affected products (3)
- cpe:2.3:a:harfbuzz_project:harfbuzz:2.9.0:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
More vulnerabilities in Harfbuzz Project Harfbuzz
- CVE-2024-56732 — High (CVSS 8.8): HarfBuzz is a text shaping engine. Starting with 8.5.0 through 10.0.1, there is a heap-based buffer overflow in the…
- CVE-2015-8947 — High (CVSS 7.6): hb-ot-layout-gpos-table.hh in HarfBuzz before 1.0.5 allows remote attackers to cause a denial of service (buffer…
- CVE-2016-2052 — High (CVSS 7.6): Multiple unspecified vulnerabilities in HarfBuzz before 1.0.6, as used in Google Chrome before 48.0.2564.82, allow…
- CVE-2023-25193 — High (CVSS 7.5): hb-ot-layout-gsubgpos.hh in HarfBuzz through 6.0.0 allows attackers to trigger O(n^2) growth via consecutive marks…
- CVE-2015-9274 — Medium (CVSS 6.5): HarfBuzz before 1.0.4 allows remote attackers to cause a denial of service (invalid read of two bytes and application…
- CVE-2022-33068 — Medium (CVSS 5.5): An integer overflow in the component hb-ot-shape-fallback.cc of Harfbuzz v4.3.0 allows attackers to cause a Denial of…
All CVEs affecting Harfbuzz Project Harfbuzz →
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…