World-writable permissions on the /tmp/tmate/sessions directory in tmate-ssh-server 2.3.0 allow a local attacker to compromise the integrit…

published 2021-12-07 4y ago modified 2026-06-17 4mo ago also EUVD-2021-31345

cvss: 7.0; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 18%
public exploits: 0; none known

World-writable permissions on the /tmp/tmate/sessions directory in tmate-ssh-server 2.3.0 allow a local attacker to compromise the integrity of session handling, or obtain the read-write session ID from a read-only session symlink in this directory.

Patch / fix

distros 1 links 1

tmate-ssh-server Debian 14, Debian 13 2.3.0-68-gd7334ee4-1

debian advisories DEBIAN-CVE-2021-44512

github.com/tmate-io/tmate-ssh-server@1c020d1 commit

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Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.0	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	4.4	AV:L/AC:M/Au:N/C:P/I:P/A:P

Classification

Weakness

CWE-732 Incorrect Permission Assignment for Critical Resource

References

github.com /tmate-io/tmate-ssh-server/commit/1c020d1f5ca462f5b150b46a027aaa1bbe3c9596
patch, third-party-advisory
openwall.com /lists/oss-security/2021/12/06/2
mailing-list, third-party-advisory

Sources

CVE List CVE-2021-44512
NVD CVE-2021-44512

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