6.5
MEDIUM CVSS 3.1
CVE-2026-9539
libslirp TCP URG OOB Read Information Leak
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).

INFO

Published Date :

June 24, 2026, 4:37 a.m.

Last Modified :

June 24, 2026, 4:37 a.m.

Remotely Exploit :

No

Source :

STAR_Labs
Affected Products

The following products are affected by CVE-2026-9539 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM b1571b85-cbc9-431f-830b-0c8155323a69
CVSS 3.1 MEDIUM [email protected]
Solution
Update libslirp to version v4.9.2 or later to fix heap read and integer underflow vulnerabilities.
  • Update libslirp to v4.9.2 or later.
  • Apply vendor-provided patches for libslirp.
  • Limit guest VM network privileges if possible.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-9539 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.