Medium
putty — security advisory
PuTTY 0.72 before 0.84 has a double free in RSA KEX.
- Products
- putty
- Affected versions
- 0.65-2, 0.66-1, 0.66-2, 0.66-3, 0.66-4, 0.67-1, 0.67-2, 0.67-3+deb9u1build0.16.04.1, 0.67-3build0.16.04.1, 0.70-1, 0.70-2, 0.70-3, 0.70-4, 0.72-1, 0.73-1, 0.73-2, 0.75-3, 0.76-1, 0.76-2, 0.78-3, 0.79-1, 0.80-1, 0.80-1build2, 0.80-1build3, 0.81-1, 0.83-2, 0.83-3, 0.83-3build1, 0.84-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-48850
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 00:50 UTC · Revision 1
Source evidence
PuTTY 0.72 before 0.84 has a double free in RSA KEX.
osv:UBUNTU-CVE-2026-48850
putty
Fixed versions: Not specified
putty
Fixed versions: Not specified
putty
Fixed versions: Not specified
putty
Fixed versions: Not specified
putty
Fixed versions: Not specified
putty
Fixed versions: Not specified
putty
Fixed versions: Not specified
putty
Fixed versions: Not specified
Complete source record
{
"id": "bd154cfd1f3220283d14550c8dae1ef534725a2a45236b98f9eb80e4ff0cb433",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-48850",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-48850",
"summary": "PuTTY 0.72 before 0.84 has a double free in RSA KEX.",
"evidence": "osv:UBUNTU-CVE-2026-48850",
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{
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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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{
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{
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{
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{
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{
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{
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{
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"evidence": "/affected/4/versions"
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{
"value": "0.80-1build2",
"evidence": "/affected/4/versions"
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{
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"evidence": "/affected/4/versions"
},
{
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"evidence": "/affected/4/versions"
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]
},
{
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},
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"affected_versions": [
{
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{
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},
{
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"evidence": "/affected/6/package/name"
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"prerequisites": [],
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"affected_versions": [
{
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"evidence": "/affected/6/versions"
},
{
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"evidence": "/affected/6/versions"
}
]
},
{
"name": {
"value": "putty",
"evidence": "/affected/7/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "0.83-3",
"evidence": "/affected/7/versions"
},
{
"value": "0.83-3build1",
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}
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],
"severity": "medium",
"structured": {
"id": "UBUNTU-CVE-2026-48850",
"aliases": [
"UBUNTU-CVE-2026-48850"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
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"affected": [
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"events": [
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},
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"0.65-2",
"0.66-1",
"0.66-2",
"0.66-3",
"0.66-4",
"0.67-1",
"0.67-2",
"0.67-3build0.16.04.1",
"0.67-3+deb9u1build0.16.04.1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48850.json"
},
"ecosystem_specific": {
"binaries": [
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"binary_version": "0.67-3+deb9u1build0.16.04.1"
},
{
"binary_name": "putty",
"binary_version": "0.67-3+deb9u1build0.16.04.1"
},
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}
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}
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{
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"0.70-2",
"0.70-3",
"0.70-4"
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"database_specific": {
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},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "pterm",
"binary_version": "0.70-4"
},
{
"binary_name": "putty",
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},
{
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{
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},
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"0.73-1",
"0.73-2"
],
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},
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"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
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"0.76-1",
"0.76-2"
],
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},
"ecosystem_specific": {
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}
],
"modified": "2026-10-17T12:56:06.846956058Z",
"provider": "osv",
"upstream": [
"CVE-2026-48850"
],
"references": [
"https://ubuntu.com/security/CVE-2026-48850",
"https://www.cve.org/CVERecord?id=CVE-2026-48850",
"https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html",
"https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/rsakex-double-free.html"
]
},
"related_cves": [
{
"value": "CVE-2026-48850",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/1/score"
},
"source_id": "core-osv",
"document_id": 354836,
"published_at": "2026-05-25T21:16:00+00:00"
}