CriticalFix available
screen — security advisory
encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 character sequence.
- Products
- screen
- Affected versions
- Not specified
- Fixed versions
- 4.6.2-r2, 4.7.0-r2, 4.8.0-r1, 4.8.0-r4
- CVEs
- CVE-2021-26937
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:03 UTC · Revision 1
Source evidence
encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 character sequence.
osv:ALPINE-CVE-2021-26937
screen
Fixed versions: 4.6.2-r2
screen
Fixed versions: 4.7.0-r2
screen
Fixed versions: 4.8.0-r1
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
screen
Fixed versions: 4.8.0-r4
Complete source record
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],
"modified": "2026-10-23T17:17:56.164319601Z",
"provider": "osv",
"upstream": [
"CVE-2021-26937"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2021-26937"
]
},
"related_cves": [
{
"value": "CVE-2021-26937",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 415358,
"published_at": "2021-02-09T20:15:14.91+00:00"
}