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Vulnerability record · CVE-2021-27135 · published 10 February 2021

CVE-2021-27135: Invisible-island xterm vulnerability

Invisible Island · Xterm

xterm before Patch #366 allows remote attackers to execute arbitrary code or cause a denial of service (segmentation fault) via a crafted UTF-8 combining character sequence.

9.8 CVSS 3.1 Critical EPSS 7.8% · top 5.5%
9.8CVSS 3.1 base score, v2 7.5
7.8%EPSS exploitation probability, 30 days
NoNot in CISA KEV
3Affected product versions listed by NVD
26References
17 Jun 2026Last modified by NVD

Description

xterm before Patch #366 allows remote attackers to execute arbitrary code or cause a denial of service (segmentation fault) via a crafted UTF-8 combining character sequence.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

3 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://seclists.org/fulldisclosure/2021/May/52 Mailing ListThird Party Advisory
http://www.openwall.com/lists/oss-security/2021/02/10/7 Mailing ListThird Party Advisory
https://access.redhat.com/security/cve/CVE-2021-27135 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1927559 Issue Tracking
https://bugzilla.suse.com/show_bug.cgi?id=1182091 Issue Tracking
https://github.com/ThomasDickey/xterm-snapshots/commit/82ba55b8f994ab30ff561a347b82ea340ba7075c PatchThird Party Advisory
https://invisible-island.net/xterm/xterm.log.html Release NotesVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00019.html Mailing ListThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/35LK2ZXEIJUOGOA7FV2TJL3
https://news.ycombinator.com/item?id=26524650 Issue TrackingThird Party Advisory
https://security.gentoo.org/glsa/202208-22 Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/02/09/7 Mailing ListThird Party Advisory
https://www.openwall.com/lists/oss-security/2021/02/09/9 Mailing ListThird Party Advisory
http://seclists.org/fulldisclosure/2021/May/52 Mailing ListThird Party Advisory
http://www.openwall.com/lists/oss-security/2021/02/10/7 Mailing ListThird Party Advisory
https://access.redhat.com/security/cve/CVE-2021-27135 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1927559 Issue Tracking
https://bugzilla.suse.com/show_bug.cgi?id=1182091 Issue Tracking
https://github.com/ThomasDickey/xterm-snapshots/commit/82ba55b8f994ab30ff561a347b82ea340ba7075c PatchThird Party Advisory
https://invisible-island.net/xterm/xterm.log.html Release NotesVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00019.html Mailing ListThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/35LK2ZXEIJUOGOA7FV2TJL3
https://news.ycombinator.com/item?id=26524650 Issue TrackingThird Party Advisory
https://security.gentoo.org/glsa/202208-22 Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/02/09/7 Mailing ListThird Party Advisory
https://www.openwall.com/lists/oss-security/2021/02/09/9 Mailing ListThird Party Advisory

Track CVE-2021-27135 inside VULONE

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Source: NIST National Vulnerability Database (record CVE-2021-27135), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.