SARA / Free Tools / CVE / CVE-2023-3255

CVE-2023-3255 — A flaw was found in the QEMU built-in VNC server while processing ClientCutText

A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is

CVSS
6.5 MEDIUM
EPSS
12.00% (top 69.70%)
CWE
CWE-835
Published
2023-09-13T16:12:52.294Z
Last modified
2025-11-08T06:30:19.755Z
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

01What is this vulnerability?

A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service.

02Affected products

VendorProductVersions
Red HatRed Hat Enterprise Linux 88100020240314161907.e155f54d
Red HatRed Hat Enterprise Linux 88100020240314161907.e155f54d
Red HatRed Hat Enterprise Linux 917:8.2.0-11.el9_4
Red HatRed Hat Enterprise Linux 6unspecified
Red HatRed Hat Enterprise Linux 7unspecified
Red HatRed Hat Enterprise Linux 7unspecified
Red HatRed Hat Enterprise Linux 8 Advanced Virtualizationunspecified

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

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07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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