LowFix available
curl — security advisory
curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.
- Products
- curl
- Affected versions
- Not specified
- Fixed versions
- 7.66.0-r4, 7.67.0-r4, 7.77.0-r0
- CVEs
- CVE-2021-22898
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:02 UTC · Revision 1
Source evidence
curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.
osv:ALPINE-CVE-2021-22898
curl
Fixed versions: 7.66.0-r4
curl
Fixed versions: 7.67.0-r4
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
curl
Fixed versions: 7.77.0-r0
Complete source record
{
"id": "2b311fb03dbc7a9fb861a6bde4a523f196a33a9a004e3ad2e2c050438c118640",
"url": "https://osv.dev/vulnerability/ALPINE-CVE-2021-22898",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "ALPINE-CVE-2021-22898",
"summary": "curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.",
"evidence": "osv:ALPINE-CVE-2021-22898",
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{
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{
"name": {
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"severity": "low",
"structured": {
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"aliases": [
"ALPINE-CVE-2021-22898"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N"
}
],
"affected": [
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"ecosystem": "Alpine:v3.10"
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},
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{
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{
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"ecosystem": "Alpine:v3.24"
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}
],
"modified": "2026-10-23T17:17:56.151132573Z",
"provider": "osv",
"upstream": [
"CVE-2021-22898"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2021-22898"
]
},
"related_cves": [
{
"value": "CVE-2021-22898",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 415304,
"published_at": "2021-06-11T16:15:11.043+00:00"
}