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CVE-2021-26937encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash)…
- 9.8CriticalCVSS base score
- 9.3%Exploitation in 30 daysEPSS · top 4.6% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By mitre
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 9.3% · top 4.6% of all CVEs (13 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
n/a
- affected n/a
References
References10
- https://lists.gnu.org/archive/html/screen-devel/2021-02/msg00000.html (opens in a new tab)x_refsource_MISCx_transferred
- https://www.openwall.com/lists/oss-security/2021/02/09/3 (opens in a new tab)x_refsource_MISCx_transferred
- https://ftp.gnu.org/gnu/screen/ (opens in a new tab)x_refsource_MISCx_transferred
- [oss-security] 20210210 Re: screen crash processing combining characters (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [debian-lts-announce] 20210219 [SECURITY] [DLA 2570-1] screen security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- DSA-4861 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- FEDORA-2021-5e9894a0c5 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- FEDORA-2021-9107eeb95c (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- GLSA-202105-11 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- https://security.netapp.com/advisory/ntap-20250509-0004/ (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-13719 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-26937)Record last updated .