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CVE-2025-26599

high

An access to an uninitialized pointer flaw was found in X.Org and Xwayland.

Vendor / product: Tigervnc — tigervnc

An access to an uninitialized pointer flaw was found in X.Org and Xwayland. The function compCheckRedirect() may fail if it cannot allocate the backing pixmap. In that case, compRedirectWindow() will return a BadAlloc error without validating the window tree marked just before, which leaves the validated data partly initialized and the use of an uninitialized pointer later.

CVSS
7.8
7.8 (CVSS v3.1)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2025-02-25 16:15
Modified: 2026-11-04 22:17
NVD status: Modified
Last synced 4 hours ago
Verified against the source API 2026-11-04 22:37 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

tigervnc / tigervnc all versions
x.org / x_server <21.1.16
x.org / xwayland <24.1.6
redhat / enterprise_linux 7.0, 8.0, 9.0

Weakness classification (CWE)

CWE-824

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

Data sources

NVD CVE API 2.0 — fetched 2026-11-04 22:37 UTC · record ↗

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Understanding CVEs and CVSS Scores

Related CVEs

CVE-2025-26601CVE-2025-26600CVE-2025-26598CVE-2025-26597CVE-2025-26596