CVE-2026-9539

An out-of-bounds heap read and integer underflow in the TCP urgent data handling (sosendoob) in freedesktop.org libslirp version before v4.9.2 on hypervisor host environments (e.g., QEMU) allows a privileged guest VM attacker (root or CAP_NET_RAW) to leak gigabytes of sensitive host-process heap memory via sending crafted TCP segments with manipulated URG flags and urgent pointers (ti_urp).

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.0 / Impact : 4.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://gitlab.freedesktop.org/slirp/libslirp/-/commit/927bca7344e31fd58e2f7afaca784aad4400eb84
https://gitlab.freedesktop.org/slirp/libslirp/-/releases/v4.9.2
https://gitlab.freedesktop.org/slirp/libslirp/-/work_items/93
https://gitlab.freedesktop.org/slirp/libslirp/-/work_items/93

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-24 05:17

Updated : 2026-06-25 19:26

NVD link : CVE-2026-9539

Mitre link : CVE-2026-9539

CVE.ORG link : CVE-2026-9539

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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