High
libslirp — security advisory
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.
- Products
- libslirp
- Affected versions
- 4.0.0-1, 4.0.0-2, 4.1.0-1, 4.1.0-2, 4.1.0-2ubuntu1, 4.1.0-2ubuntu2, 4.1.0-2ubuntu2.1, 4.1.0-2ubuntu2.2, 4.4.0-1build1, 4.6.1-1, 4.6.1-1build1, 4.6.1-1ubuntu0.2, 4.7.0-1ubuntu1, 4.7.0-1ubuntu2, 4.7.0-1ubuntu3, 4.7.0-1ubuntu3.1, 4.8.0-1ubuntu1, 4.9.1-1ubuntu1, 4.9.1-1ubuntu1.1, 4.9.3-1ubuntu1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-95508
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 19:44 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-95508
libslirp
Fixed versions: Not specified
libslirp
Fixed versions: Not specified
libslirp
Fixed versions: Not specified
libslirp
Fixed versions: Not specified
libslirp
Fixed versions: Not specified
Complete source record
{
"id": "461157d0e503057e776a490bf8d96b6dc214880e67a931182cd17618e010132f",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-95508",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-95508",
"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.",
"evidence": "osv:UBUNTU-CVE-2026-95508",
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{
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],
"severity": "high",
"structured": {
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"aliases": [
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"metrics": [
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"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
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],
"affected": [
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],
"modified": "2026-10-22T23:20:38.069728185Z",
"provider": "osv",
"upstream": [
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],
"references": [
"https://ubuntu.com/security/CVE-2026-95508",
"https://www.cve.org/CVERecord?id=CVE-2026-95508",
"https://access.redhat.com/security/cve/CVE-2026-95508"
]
},
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"source_id": "core-osv",
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"published_at": "2026-09-22T09:17:00+00:00"
}