High
nix — security advisory
An issue was discovered in Nix before 2.34.7 and Lix before 2.95.2. Unbounded recursion in the NAR (Nix Archive) parser could lead to a stack-to-heap overflow when the parser is run on a coroutine stack. The stack is allocated without a guard page, which means that a stack overflow could overwrite memory on the heap and could allow arbitrary code execution as the Nix daemon (run as root in multi-user installations) if ASLR hardening is bypassed. This can be exploited by all users able to connect to the daemon (e.g., in Nix, this is configurable via the allowed-users setting, defaulting to all users). The fixed versions are 2.34.7, 2.33.6, 2.32.8, 2.31.5, 2.30.5, 2.29.4, and 2.28.7 for Nix (introduced in 2.24.4); and 2.95.2, 2.94.2, and 2.93.4 for Lix (introduced in 2.93.0).
- Products
- nix
- Affected versions
- 2.16.1+dfsg-3ubuntu1, 2.18.1+dfsg-1ubuntu1, 2.18.1+dfsg-1ubuntu2, 2.18.1+dfsg-1ubuntu4, 2.18.1+dfsg-1ubuntu5, 2.18.1+dfsg-1ubuntu5+esm2, 2.24.9+dfsg-2ubuntu2, 2.26.3+dfsg-1ubuntu1, 2.26.3+dfsg-1ubuntu2, 2.26.3+dfsg-1ubuntu4, 2.26.3+dfsg-1ubuntu5, 2.3.10+dfsg1-1, 2.3.10+dfsg1-1build1, 2.32.5+dfsg-1ubuntu3, 2.32.5+dfsg-2ubuntu1, 2.34.3+dfsg-1, 2.34.6+dfsg-1, 2.34.6+dfsg-1build1, 2.34.8+dfsg-1, 2.34.8+dfsg-1build1, 2.6.0+dfsg-2, 2.6.0+dfsg-3, 2.6.0+dfsg-3ubuntu0.1~esm1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-44028
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:12 UTC · Revision 1
Source evidence
An issue was discovered in Nix before 2.34.7 and Lix before 2.95.2. Unbounded recursion in the NAR (Nix Archive) parser could lead to a stack-to-heap overflow when the parser is run on a coroutine stack. The stack is allocated without a guard page, which means that a stack overflow could overwrite memory on the heap and could allow arbitrary code execution as the Nix daemon (run as root in multi-user installations) if ASLR hardening is bypassed. This can be exploited by all users able to connect to the daemon (e.g., in Nix, this is configurable via the allowed-users setting, defaulting to all users). The fixed versions are 2.34.7, 2.33.6, 2.32.8, 2.31.5, 2.30.5, 2.29.4, and 2.28.7 for Nix (introduced in 2.24.4); and 2.95.2, 2.94.2, and 2.93.4 for Lix (introduced in 2.93.0).
osv:UBUNTU-CVE-2026-44028
nix
Fixed versions: Not specified
nix
Fixed versions: Not specified
nix
Fixed versions: Not specified
nix
Fixed versions: Not specified
nix
Fixed versions: Not specified
Complete source record
{
"id": "92e225040e45c7dce37589d5d053e70b4dea826d246da4740e37bf8261788b08",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-44028",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-44028",
"summary": "An issue was discovered in Nix before 2.34.7 and Lix before 2.95.2. Unbounded recursion in the NAR (Nix Archive) parser could lead to a stack-to-heap overflow when the parser is run on a coroutine stack. The stack is allocated without a guard page, which means that a stack overflow could overwrite memory on the heap and could allow arbitrary code execution as the Nix daemon (run as root in multi-user installations) if ASLR hardening is bypassed. This can be exploited by all users able to connect to the daemon (e.g., in Nix, this is configurable via the allowed-users setting, defaulting to all users). The fixed versions are 2.34.7, 2.33.6, 2.32.8, 2.31.5, 2.30.5, 2.29.4, and 2.28.7 for Nix (introduced in 2.24.4); and 2.95.2, 2.94.2, and 2.93.4 for Lix (introduced in 2.93.0).",
"evidence": "osv:UBUNTU-CVE-2026-44028",
"products": [
{
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},
"prerequisites": [],
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"affected_versions": [
{
"value": "2.3.10+dfsg1-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.3.10+dfsg1-1build1",
"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
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{
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"value": "2.16.1+dfsg-3ubuntu1",
"evidence": "/affected/1/versions"
},
{
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"evidence": "/affected/1/versions"
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{
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"evidence": "/affected/1/versions"
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{
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"evidence": "/affected/1/versions"
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{
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{
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{
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"evidence": "/affected/3/versions"
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{
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},
{
"name": {
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"evidence": "/affected/4/package/name"
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"prerequisites": [],
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"affected_versions": [
{
"value": "2.26.3+dfsg-1ubuntu4",
"evidence": "/affected/4/versions"
},
{
"value": "2.26.3+dfsg-1ubuntu5",
"evidence": "/affected/4/versions"
},
{
"value": "2.32.5+dfsg-1ubuntu3",
"evidence": "/affected/4/versions"
},
{
"value": "2.32.5+dfsg-2ubuntu1",
"evidence": "/affected/4/versions"
},
{
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"evidence": "/affected/4/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2026-44028",
"aliases": [
"UBUNTU-CVE-2026-44028"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
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"ecosystem": "Ubuntu:Pro:22.04:LTS"
},
"versions": [
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"2.6.0+dfsg-2",
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"2.6.0+dfsg-3ubuntu0.1~esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44028.json"
},
"ecosystem_specific": {
"binaries": [
{
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},
{
"binary_name": "nix-setup-systemd",
"binary_version": "2.6.0+dfsg-3ubuntu0.1~esm1"
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]
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},
{
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],
"modified": "2026-10-17T12:58:18.428466419Z",
"provider": "osv",
"upstream": [
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],
"references": [
"https://ubuntu.com/security/CVE-2026-44028",
"https://www.cve.org/CVERecord?id=CVE-2026-44028",
"https://discourse.nixos.org/t/security-advisory-local-privilege-escalation-in-lix-and-nix/77407",
"https://github.com/NixOS/nix/security/advisories/GHSA-vh5x-56v6-4368",
"https://www.openwall.com/lists/oss-security/2026/05/04/33"
]
},
"related_cves": [
{
"value": "CVE-2026-44028",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 358526,
"published_at": "2026-05-05T01:16:00+00:00"
}