CVE-2021-26955
CVE-2021-26955 is a critical-severity vulnerability in Xcb Project Xcb with a CVSS 3.x base score of 9.8. 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-252.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 2% (75th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-252
- Affected product: Xcb Project Xcb
- Published:
- Last modified:
Description
An issue was discovered in the xcb crate through 2021-02-04 for Rust. It has a soundness violation because xcb::xproto::GetAtomNameReply::name() calls std::str::from_utf8_unchecked() on unvalidated bytes from an X server.
Frequently asked questions
- What is CVE-2021-26955?
- An issue was discovered in the xcb crate through 2021-02-04 for Rust. It has a soundness violation because xcb::xproto::GetAtomNameReply::name() calls std::str::from_utf8_unchecked() on unvalidated bytes from an X server.
- How severe is CVE-2021-26955?
- CVE-2021-26955 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-26955 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-26955?
- CVE-2021-26955 affects Xcb Project Xcb. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-26955?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-26955 published?
- CVE-2021-26955 was published on 2021-02-09 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:xcb_project:xcb:*:*:*:*:*:rust:*:*
More vulnerabilities in Xcb Project Xcb
- CVE-2021-26957 — Critical (CVSS 9.8): An issue was discovered in the xcb crate through 2021-02-04 for Rust. It has a soundness violation because there is an…
- CVE-2021-26956 — Critical (CVSS 9.8): An issue was discovered in the xcb crate through 2021-02-04 for Rust. It has a soundness violation because bytes from…
- CVE-2021-26958 — High (CVSS 8.8): An issue was discovered in the xcb crate through 2021-02-04 for Rust. It has a soundness violation because…
- CVE-2020-36205 — Medium (CVSS 5.5): An issue was discovered in the xcb crate through 2020-12-10 for Rust. base::Error does not have soundness. Because of…
All CVEs affecting Xcb Project Xcb →
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