CVE-2026-9539

Published: June 26, 2026Last modified: July 2, 2026

Description

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).

Severity score breakdown

ParameterValue
Base score6.5
Attack VectorLOCAL
Attack complexityLOW
Privileges requiredLOW
User interactionNONE
ScopeCHANGED
ConfidentialityHIGH
Integrity impactNONE
Availability impactNONE
VectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

Status

ProductReleasePackageStatus
Alpaquita Linux23 LTSlibslirpFixed (4.7.0-r1)
25 LTSlibslirpFixed (4.8.0-r1)
StreamlibslirpFixed (4.9.3-r0)

References

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