CVE-2026-9539 (GCVE-0-2026-9539)
Vulnerability from cvelistv5 – Published: 2026-06-24 04:37 – Updated: 2026-06-24 12:39
VLAI
EPSS
VEX
Title
libslirp TCP URG OOB Read Information Leak
Summary
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
6.5 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-24 12:39 UTC
CWE
- CWE-125 - Out-of-bounds read
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://gitlab.freedesktop.org/slirp/libslirp/-/w… | issue-tracking |
| https://gitlab.freedesktop.org/slirp/libslirp/-/c… | patch |
| https://gitlab.freedesktop.org/slirp/libslirp/-/r… | release-notes |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| freedesktop.org | libslirp |
Affected:
0 , < 4.9.2
(semver)
|
guessed |
Date Public
2026-06-24 04:25
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
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