9.1

CVE-2021-43400: bluez Use After Free

CVSS: 9.1v3.1CriticalModified
AliasesUBUNTU-CVE-2021-43400DEBIAN-CVE-2021-43400
Published 04-11-2021Last modified 04-11-2025
Open JSON

Vulnerability summary

CVE-2021-43400 is a critical (CVSS 9.1) Use After Free vulnerability in bluez. EPSS estimates a 1.66% chance of exploitation in the next 30 days, higher than 76.3% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
1.66%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 7 · Related 4
DLA-3157-1DLA-3879-1MGASA-2021-0532SUSE-SU-2022:3687-1SUSE-SU-2022:3691-1SUSE-SU-2022:3981-1

Timeline

  1. 04-11-2021
    PublishedVulnerability first disclosed.
  2. 04-11-2025
    Last modifiedVulnerability information updated.

Description

An issue was discovered in gatt-database.c in BlueZ 5.61. A use-after-free can occur when a client disconnects during D-Bus processing of a WriteValue call.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

1.66%

Chance of exploitation in the next 30 days

Percentile

76%

Versus all other CVEs

30-day change

0.00 pp

From 1.66% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.66%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian2 products
Bluez1 product
Ubuntu1 product
  • bluezAll versions (No fix recorded) | < 5.48-0ubuntu3.6 | < 5.53-0ubuntu3.4

3 vendors · 4 products

References

7 links