Out-of-bounds read in samba
Priority MEDIUM 40CWE-125Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 20 fixed, 2 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-125 and the CVSS impact.
Summary
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.
Why it matters now
EPSS 0.04363 91st percentileScored 2026-11-07
Fix Partial Red Hat: 6 advisoriesRed Hat: 20 fixed, 2 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | samba | samba 4.14.1, samba 4.13.6, samba 4.12.13 | — | No fix listed | CNA |
- samba Vendor— Affected samba 4.14.1, samba 4.13.6, samba 4.12.13 Fixed in — No fix listed CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:* | 4.0.0 to before 4.12.13; 4.13.0 to before 4.13.6; 4.14.0 to before 4.14.1 | Vulnerable | Samba |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* | 10.0 | Vulnerable | Debian |
| cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* | 32 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | 33 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | 34 | Vulnerable | Fedoraproject |
- cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:* Versions 4.0.0 to before 4.12.13; 4.13.0 to before 4.13.6; 4.14.0 to before 4.14.1 Vulnerable ·Samba
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
- cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* Versions 32 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
Remediation
Red Hat 6 advisories
- RHSA-2021:2786 Released 2021-07-20 · Red Hat rating Importantlibldb security update
- Red Hat Enterprise Linux Server AUS (v. 7.6) libldb-1.3.4-2.el7_6, pyldb-1.3.4-2.el7_6
- Red Hat Enterprise Linux Server E4S (v. 7.6) libldb-1.3.4-2.el7_6, pyldb-1.3.4-2.el7_6
- Red Hat Enterprise Linux Server Optional AUS (v. 7.6) ldb-tools-1.3.4-2.el7_6, libldb-devel-1.3.4-2.el7_6, pyldb-devel-1.3.4-2.el7_6
- Red Hat Enterprise Linux Server Optional E4S (v. 7.6) ldb-tools-1.3.4-2.el7_6, libldb-devel-1.3.4-2.el7_6, pyldb-1.3.4-2.el7_6 +1
- Red Hat Enterprise Linux Server Optional TUS (v. 7.6) ldb-tools-1.3.4-2.el7_6, libldb-devel-1.3.4-2.el7_6, pyldb-devel-1.3.4-2.el7_6
- Red Hat Enterprise Linux Server TUS (v. 7.6) libldb-1.3.4-2.el7_6, pyldb-1.3.4-2.el7_6
- RHSA-2021:2331 Released 2021-06-08 · Red Hat rating Importantlibldb security update
- Red Hat Enterprise Linux ComputeNode EUS (v. 7.7) libldb-1.4.2-2.el7_7
- Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7) ldb-tools-1.4.2-2.el7_7, libldb-devel-1.4.2-2.el7_7, pyldb-1.4.2-2.el7_7 +1
- Red Hat Enterprise Linux Server EUS (v. 7.7) libldb-1.4.2-2.el7_7, libldb-1.4.2-2.el7_7.ppc, pyldb-1.4.2-2.el7_7
- Red Hat Enterprise Linux Server Optional EUS (v. 7.7) ldb-tools-1.4.2-2.el7_7, libldb-devel-1.4.2-2.el7_7, libldb-devel-1.4.2-2.el7_7.ppc +4
- RHSA-2021:1213 Released 2021-04-15 · Red Hat rating Importantlibldb security update
- Red Hat Enterprise Linux BaseOS EUS (v. 8.2) ldb-tools-2.0.7-4.el8_2, libldb-2.0.7-4.el8_2, libldb-devel-2.0.7-4.el8_2 +1
Show 3 more Red Hat advisories
- RHSA-2021:1214 Released 2021-04-15 · Red Hat rating Importantlibldb security update
- Red Hat Enterprise Linux BaseOS EUS (v. 8.1) ldb-tools-1.5.4-3.el8_1, libldb-1.5.4-3.el8_1, libldb-devel-1.5.4-3.el8_1 +1
- RHSA-2021:1197 Released 2021-04-14 · Red Hat rating Importantlibldb security update
- Red Hat Enterprise Linux BaseOS (v. 8) ldb-tools-2.1.3-3.el8_3, libldb-2.1.3-3.el8_3, libldb-devel-2.1.3-3.el8_3 +1
- RHSA-2021:1072 Released 2021-04-06 · Red Hat rating Importantlibldb security update
- Red Hat Enterprise Linux Client (v. 7) libldb-1.5.4-2.el7_9, pyldb-1.5.4-2.el7_9
- Red Hat Enterprise Linux Client Optional (v. 7) ldb-tools-1.5.4-2.el7_9, libldb-devel-1.5.4-2.el7_9, pyldb-devel-1.5.4-2.el7_9
- Red Hat Enterprise Linux ComputeNode Optional (v. 7) ldb-tools-1.5.4-2.el7_9, libldb-devel-1.5.4-2.el7_9, pyldb-devel-1.5.4-2.el7_9
- Red Hat Enterprise Linux Server (v. 7) libldb-1.5.4-2.el7_9, libldb-1.5.4-2.el7_9.ppc, pyldb-1.5.4-2.el7_9 +1
- Red Hat Enterprise Linux Server Optional (v. 7) ldb-tools-1.5.4-2.el7_9, libldb-devel-1.5.4-2.el7_9, libldb-devel-1.5.4-2.el7_9.ppc +2
- Red Hat Enterprise Linux Workstation (v. 7) libldb-1.5.4-2.el7_9, pyldb-1.5.4-2.el7_9
- Red Hat Enterprise Linux Workstation Optional (v. 7) ldb-tools-1.5.4-2.el7_9, libldb-devel-1.5.4-2.el7_9, pyldb-devel-1.5.4-2.el7_9
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
samba — FEDORA-2021-c93a3a5d3f
2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2020-16910 Out-of-bounds read in sambaPriority LOW 39
- Advisory ·
samba — FEDORA-2021-c2d8628d33
2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2020-16910 Out-of-bounds read in sambaPriority LOW 39
Show 1 more group
- Advisory ·
samba — FEDORA-2021-1a8e93a285
2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2020-16910 Out-of-bounds read in sambaPriority LOW 39
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Storage 3 | Affected | No fix yet |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2021:1197 |
| Red Hat Enterprise Linux BaseOS EUS (v. 8.1) | Fixed | RHSA-2021:1214 |
| Red Hat Enterprise Linux BaseOS EUS (v. 8.2) | Fixed | RHSA-2021:1213 |
| Red Hat Enterprise Linux Client (v. 7) | Fixed | RHSA-2021:1072 |
| Red Hat Enterprise Linux Client Optional (v. 7) | Fixed | RHSA-2021:1072 |
| Red Hat Enterprise Linux ComputeNode EUS (v. 7.7) | Fixed | RHSA-2021:2331 |
| Red Hat Enterprise Linux ComputeNode Optional (v. 7) | Fixed | RHSA-2021:1072 |
| Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7) | Fixed | RHSA-2021:2331 |
| Red Hat Enterprise Linux Server (v. 7) | Fixed | RHSA-2021:1072 |
| Red Hat Enterprise Linux Server AUS (v. 7.6) | Fixed | RHSA-2021:2786 |
| Red Hat Enterprise Linux Server E4S (v. 7.6) | Fixed | RHSA-2021:2786 |
| Red Hat Enterprise Linux Server EUS (v. 7.7) | Fixed | RHSA-2021:2331 |
| Red Hat Enterprise Linux Server Optional (v. 7) | Fixed | RHSA-2021:1072 |
| Red Hat Enterprise Linux Server Optional AUS (v. 7.6) | Fixed | RHSA-2021:2786 |
| Red Hat Enterprise Linux Server Optional E4S (v. 7.6) | Fixed | RHSA-2021:2786 |
| Red Hat Enterprise Linux Server Optional EUS (v. 7.7) | Fixed | RHSA-2021:2331 |
| Red Hat Enterprise Linux Server Optional TUS (v. 7.6) | Fixed | RHSA-2021:2786 |
| Red Hat Enterprise Linux Server TUS (v. 7.6) | Fixed | RHSA-2021:2786 |
| Red Hat Enterprise Linux Workstation (v. 7) | Fixed | RHSA-2021:1072 |
| Red Hat Enterprise Linux Workstation Optional (v. 7) | Fixed | RHSA-2021:1072 |
Not affected: 1 product
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-20277
- 2026-10-03 Alias added: GHSA-96fm-7x9f-hmmw
References
Advisory 9
- https://security.netapp.com/advisory/ntap-20210326-0007/
- FEDORA-2021-c2d8628d33
- [debian-lts-announce] 20210331 [SECURITY] [DLA 2611-1] ldb security update
- DSA-4884
- FEDORA-2021-1a8e93a285
- FEDORA-2021-c93a3a5d3f
- https://bugzilla.redhat.com/show_bug.cgi?id=1941402
- https://www.samba.org/samba/security/CVE-2021-20277.html
- GLSA-202105-22
Sources
- CVE-2021-20277 · CVE Program
- CVE-2021-20277 · NVD
- FIRST EPSS
- GHSA-96fm-7x9f-hmmw · GitHub Advisory Database · CC BY 4.0
- CVE-2021-20277 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences