CVE-2025-49177 | Xorg-x11-server-xwayland: xorg-x11-server: tigervnc: data leak in xfixes extension's xfixessetclientdisconnectmode

A flaw was found in the XFIXES extension. The XFixesSetClientDisconnectMode handler does not validate the request length, allowing a client to read unintended memory from previous requests.

Published: 2025-06-17 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-49177 is rated Low Risk (33.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.09%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-49177

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-13 0.01% 0.09% +0.07%
2 2025-06-18 — 0.01% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-49177

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.8 4.2 [email protected]

Weakness enumeration for CVE-2025-49177

OS Trackers for CVE-2025-49177

vendor priority summary link
alpine — CVE-2025-49177: 2 source package rows (xorg-server, xwayland); 4 state rows across 2 repos (3.22-community, edge-community); fixed 4, open 0. https://security.alpinelinux.org/vuln/CVE-2025-49177
debian unimportant CVE-2025-49177 unimportant priority: Debian including 2 source packages (xorg-server, xwayland), 9 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 7, open 2. https://security-tracker.debian.org/tracker/CVE-2025-49177
redhat high — https://access.redhat.com/security/cve/CVE-2025-49177
suse medium CVE-2025-49177 severity moderate: SUSE including 263 source package names (21.1-46.1:xorg-x11-server-21.1.11-150600.5.12.1, 21.1-46.1:xorg-x11-server-Xvfb-21.1.11-150600.5.12.1, …), 352 product×package rows across 49 product lines (Container suse/kiosk/xorg, Image SLES15-SP5-SAPCAL-Azure, … (49 product lines)): Known Affected 231, Fixed 73, Known Not Affected 48. https://www.suse.com/security/cve/CVE-2025-49177/
ubuntu medium CVE-2025-49177 medium priority: Ubuntu including 7 source packages (xorg, xorg-hwe-16.04, …), 53 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 20, not-affected 13, released 12, needs-triage 8. https://ubuntu.com/security/CVE-2025-49177

Affected software / configurations for CVE-2025-49177

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-49177

cvelogic Threat Intelligence