7.5

CVE-2021-20277: debian debian_linux Out-of-bounds Read

Modified
AliasesALPINE-CVE-2021-20277RHSA-2021:1072RHSA-2021:1197
Published 12-05-2021Last modified 03-08-2024

Vulnerability summary

CVE-2021-20277 is a high (CVSS 7.5) Out-of-bounds Read vulnerability in debian debian_linux. EPSS estimates a 4.33% chance of exploitation in the next 30 days, higher than 91.1% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 4% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
4.33%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 18 · Related 15
DLA-2611-1DSA-4884-1MGASA-2021-0287OPENSUSE-SU-2021:0469-1OPENSUSE-SU-2021:0636-1OPENSUSE-SU-2021:3187-1

Timeline

  1. 12-05-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

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 metrics

6 scores · 5 sources · 2 versions

EPSS trend

Probability

4.33%

Chance of exploitation in the next 30 days

Percentile

91%

Versus all other CVEs

30-day change

No change 0.00 pp

From 4.33% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Redhat10 products
  • ldb-tools< 0:1.5.4-2.el7_9 | < 0:2.1.3-3.el8_3 | < 0:2.0.7-4.el8_2 | < 0:1.5.4-3.el8_1 | < 0:1.4.2-2.el7_7 | < 0:1.3.4-2.el7_6
  • ldb-tools-debuginfo< 0:2.1.3-3.el8_3 | < 0:2.0.7-4.el8_2 | < 0:1.5.4-3.el8_1
  • libldb< 0:1.5.4-2.el7_9 | < 0:2.1.3-3.el8_3 | < 0:2.0.7-4.el8_2 | < 0:1.5.4-3.el8_1 | < 0:1.4.2-2.el7_7 | < 0:1.3.4-2.el7_6
  • libldb-debuginfo< 0:1.5.4-2.el7_9 | < 0:2.1.3-3.el8_3 | < 0:2.0.7-4.el8_2 | < 0:1.5.4-3.el8_1 | < 0:1.4.2-2.el7_7 | < 0:1.3.4-2.el7_6
  • libldb-debugsource< 0:2.1.3-3.el8_3 | < 0:2.0.7-4.el8_2 | < 0:1.5.4-3.el8_1
Debian2 products
Alpine1 product
  • samba≥ 4.0.0, < 4.12.14-r0 | ≥ 4.0.0, < 4.13.7-r0 | ≥ 4.0.0, < 4.14.2-r0
Fedoraproject1 product
Samba1 product
  • samba≥ 4.0.0, < 4.12.13 | ≥ 4.13.0, < 4.13.6 | ≥ 4.14.0, < 4.14.1
Ubuntu1 product
  • ldb< 1:1.1.24-0ubuntu0.14.04.2+esm1 | < 2:1.1.24-1ubuntu3.2 | < 2:1.2.3-1ubuntu0.2 | < 2:2.0.10-0ubuntu0.20.04.3

6 vendors · 16 products

References

30 links
Show all 30 references