Libslirp: libslirp: heap buffer overflow in dhcpv6/tftp response builders on small interface mtu
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
A heap-based buffer overflow was found in the DHCPv6 and TFTP response builders of libslirp. When the host is configured with a small interface MTU, a guest-supplied DHCPv6 CLIENTID option or TFTP blksize option can overflow the reply buffer with attacker-controlled content and length, resulting in denial of service and potentially arbitrary code execution in the host process. The default interface MTU is not affected.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 5 | — | — | No fix listed | CNA |
- Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 5 VendorRed Hat Affected — Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 8 | Affected | No fix yet |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-95508
- 2026-10-03 Alias added: GHSA-3qjr-gg7g-qcrr
- 2026-11-03 Affected versions changed · CNA
- 2026-11-03 Affected versions changed · Red Hat
References
More Red Hat vulnerabilities
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- TI-2019-15874 Protection mechanism failure in Jenkins Script Security Plugin KEVCVSS 3.1CRITICAL 9.9
- TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
- TI-2019-05363 Code injection in Elastic Kibana KEVCVSS 3.1CRITICAL 10.0
- TI-2019-03949 Out-of-bounds write in ESXi and Horizon DaaS KEVCVSS 3.1CRITICAL 9.8
- TI-2018-16080 A code execution vulnerability exists in the Stapler web framework used by Jenkins 2.153… KEVCVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-95508 · CVE Program
- CVE-2026-95508 · NVD
- FIRST EPSS
- GHSA-3qjr-gg7g-qcrr · GitHub Advisory Database · CC BY 4.0
- CVE-2026-95508 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences