CVE-2020-9366

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-02-24 · updated 2026-06-17
Weakness: CWE-787

Description

A buffer overflow was found in the way GNU Screen before 4.8.0 treated the special escape OSC 49. Specially crafted output, or a special program, could corrupt memory and crash Screen or possibly have unspecified other impact.

Affected products

GNU Screen: before 4.8.0 — fixed in 4.8.0

How to fix

Upgrade to a fixed version: GNU Screen 4.8.0. Check the vendor advisory for mitigations.

References

http://www.openwall.com/lists/oss-security/2020/02/25/1
https://lists.gnu.org/archive/html/screen-devel/2020-02/msg00007.html
https://security.gentoo.org/glsa/202003-62
https://www.openwall.com/lists/oss-security/2020/02/06/3
http://www.openwall.com/lists/oss-security/2020/02/25/1
https://lists.gnu.org/archive/html/screen-devel/2020-02/msg00007.html
https://security.gentoo.org/glsa/202003-62
https://www.openwall.com/lists/oss-security/2020/02/06/3

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