CVE-2021-33186
CVE-2021-33186 is a high-severity vulnerability in Serenityos 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-787.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (59th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Serenityos
- Published:
- Last modified:
Description
SerenityOS in test-crypto.cpp contains a stack buffer overflow which could allow attackers to obtain sensitive information.
Frequently asked questions
- What is CVE-2021-33186?
- SerenityOS in test-crypto.cpp contains a stack buffer overflow which could allow attackers to obtain sensitive information.
- How severe is CVE-2021-33186?
- CVE-2021-33186 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 high, integrity none, and availability none.
- Is CVE-2021-33186 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-33186?
- CVE-2021-33186 affects Serenityos. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-33186?
- 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-2021-33186 published?
- CVE-2021-33186 was published on 2021-06-18 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:serenityos:serenityos:-:*:*:*:*:*:*:*
More vulnerabilities in Serenityos
- CVE-2021-31272 — Critical (CVSS 9.8): SerenityOS before commit 3844e8569689dd476064a0759d704bc64fb3ca2c contains a directory traversal vulnerability in…
- CVE-2021-30045 — Critical (CVSS 9.1): SerenityOS 2021-03-27 contains a buffer overflow vulnerability in the EndOfCentralDirectory::read() function.
- CVE-2021-28874 — High (CVSS 7.8): SerenityOS fixed as of c9f25bca048443e317f1994ba9b106f2386688c3 contains a buffer overflow vulnerability in LibTextCode…
- CVE-2019-20172 — High (CVSS 7.8): Kernel/VM/MemoryManager.cpp in SerenityOS before 2019-12-30 does not reject syscalls with pointers into the kernel-only…
- CVE-2021-33185 — High (CVSS 7.5): SerenityOS contains a buffer overflow in the set_range test in TestBitmap which could allow attackers to obtain…
- CVE-2021-27343 — High (CVSS 7.5): SerenityOS Unspecified is affected by: Buffer Overflow. The impact is: obtain sensitive information…
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