CVE-2026-95508
Libslirp: libslirp: heap buffer overflow in dhcpv6/tftp response builders on small interface mtu
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Libslirp: libslirp: heap buffer overflow in dhcpv6/tftp response builders on small interface mtu
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.
- Record
CVE-2026-95508- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-06
EUVDEUVD-2026-84336
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.
- Record
EUVD-2026-84336- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-06
GitHub AdvisoriesGHSA-3qjr-gg7g-qcrr
A heap-based buffer overflow was found in the DHCPv6 and TFTP response builders of libslirp. When...
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.
- Record
GHSA-3qjr-gg7g-qcrr- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-95508- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-06
OSVDEBIAN-CVE-2026-95508
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.
- Record
DEBIAN-CVE-2026-95508- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-03
OSVUBUNTU-CVE-2026-95508
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.
- Record
UBUNTU-CVE-2026-95508- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-02
OSVAZL-103472 No score
CVE-2026-95508 affecting package libslirp 4.9.6-1
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.
- Record
AZL-103472- Updated
- 2026-11-05
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
libslirpAzure Linux:3 |
through 4.9.6-1 | None known |
libslirpDebian:12 |
All versions, plus listed versions 4.7.0-14.8.0-14.9.1-14.9.2-14.9.3-14.9.4-14.9.5-1 |
None known |
libslirpDebian:13 |
All versions, plus listed versions 4.8.0-14.8.0-1+deb13u14.9.1-14.9.2-14.9.3-14.9.4-14.9.5-1 |
None known |
libslirpDebian:14 |
before 4.9.5-1, plus listed versions 4.8.0-14.9.1-14.9.2-14.9.3-14.9.4-1 |
4.9.5-1 |
libslirpUbuntu:20.04:LTS |
All versions, plus listed versions 4.0.0-14.0.0-24.1.0-14.1.0-24.1.0-2ubuntu14.1.0-2ubuntu24.1.0-2ubuntu2.14.1.0-2ubuntu2.2 |
None known |
libslirpUbuntu:22.04:LTS |
All versions, plus listed versions 4.4.0-1build14.6.1-14.6.1-1build14.6.1-1ubuntu0.2 |
None known |
libslirpUbuntu:24.04:LTS |
All versions, plus listed versions 4.7.0-1ubuntu14.7.0-1ubuntu24.7.0-1ubuntu34.7.0-1ubuntu3.1 |
None known |
libslirpUbuntu:26.10 |
All versions, plus listed versions 4.9.1-1ubuntu14.9.3-1ubuntu1 |
None known |
libslirpUbuntu:26.04:LTS |
All versions, plus listed versions 4.8.0-1ubuntu14.9.1-1ubuntu14.9.1-1ubuntu1.1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | OSV | |
| products | CVE List, EUVD, NVD | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-95508 is a high vulnerability (CVSS 7.4) in Red Hat Enterprise Linux 10, published September 22, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.57%, the 47th percentile. Fixed in libslirp 4.9.5-1.