CVE-2021-26955
CVSS v3
9.8
CRITICAL
EPSS Score
1.7 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2021-02-09
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.
Is CVE-2021-26955 actively exploited?
Active exploitation of CVE-2021-26955 has not been confirmed. Its EPSS score was 1.7% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-26955?
CVE-2021-26955 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-26955 affecting your environment?
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