UnratedFix available
tor — security advisory
The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to "underflow errors."
- Products
- tor
- Affected versions
- Not specified
- Fixed versions
- 0.2.1.29-1
- CVEs
- CVE-2011-0491
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 23:18 UTC · Revision 1
Source evidence
The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to "underflow errors."
osv:DEBIAN-CVE-2011-0491
tor
Fixed versions: 0.2.1.29-1
tor
Fixed versions: 0.2.1.29-1
tor
Fixed versions: 0.2.1.29-1
Complete source record
{
"id": "2ac8c20b91142277fd210abfdfe155870e460d4beedb1caf9b6d75b9a4386ad2",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2011-0491",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2011-0491",
"summary": "The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to \"underflow errors.\"",
"evidence": "osv:DEBIAN-CVE-2011-0491",
"products": [
{
"name": {
"value": "tor",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.2.1.29-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "tor",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.2.1.29-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "tor",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.2.1.29-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "DEBIAN-CVE-2011-0491",
"aliases": [
"DEBIAN-CVE-2011-0491"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.2.1.29-1"
}
]
}
],
"package": {
"name": "tor",
"purl": "pkg:deb/debian/tor?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2011-0491.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.2.1.29-1"
}
]
}
],
"package": {
"name": "tor",
"purl": "pkg:deb/debian/tor?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2011-0491.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.2.1.29-1"
}
]
}
],
"package": {
"name": "tor",
"purl": "pkg:deb/debian/tor?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2011-0491.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T17:47:40.202546429Z",
"provider": "osv",
"upstream": [
"CVE-2011-0491"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2011-0491"
]
},
"related_cves": [
{
"value": "CVE-2011-0491",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 418254,
"published_at": "2011-01-19T12:00:20.047+00:00"
}