CVE-2021-20277
Estado: ModificadaAlta (7.5)—
A flaw was found in Samba's libldb. Multiple, consecutive leading spaces in an LDAP attribute can lead to an out-of-bounds memory write, leading to a crash of the LDAP server process handling the request. The highest threat from this vulnerability is to system availability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 4.33%
- Percentil entre todas las CVEs puntuadas: 91
- Fecha de la puntuación: 7/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (3)
CWE
- CWE-125
- CWE-787
Referencias
- https://bugzilla.redhat.com/show_bug.cgi?id=1941402
- https://lists.debian.org/debian-lts-announce/2021/03/msg00036.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/
- https://security.gentoo.org/glsa/202105-22
- https://security.netapp.com/advisory/ntap-20210326-0007/
- https://www.debian.org/security/2021/dsa-4884
- https://www.samba.org/samba/security/CVE-2021-20277.html
- https://bugzilla.redhat.com/show_bug.cgi?id=1941402
- https://lists.debian.org/debian-lts-announce/2021/03/msg00036.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/
- https://security.gentoo.org/glsa/202105-22
- https://security.netapp.com/advisory/ntap-20210326-0007/
- https://www.debian.org/security/2021/dsa-4884
- https://www.samba.org/samba/security/CVE-2021-20277.html
JSON original (NVD)
Mostrar
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