Description
A flaw was discovered in OpenLDAP before 2.4.57 leading to an infinite loop in slapd with the cancel_extop Cancel operation, resulting in denial of service.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | openldap | 2.4.57+dfsg-1 | — |
| Debian 13 | openldap | 2.4.57+dfsg-1 | — |
| Debian 12 | openldap | 2.4.57+dfsg-1 | — |
| Debian 10 | openldap | 2.4.47+dfsg-3+deb10u5 | DSA-4845-1 |
| Debian 9 | openldap | 2.4.44+dfsg-5+deb9u7 | DLA-2544-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | openldap | 2.4.49+dfsg-2ubuntu1.6 | USN-4724-1 |
| Ubuntu 18.04 LTS | openldap | 2.4.45+dfsg-1ubuntu1.9 | USN-4724-1 |
| Ubuntu 16.04 LTS | openldap | 2.4.42+dfsg-2ubuntu3.12 | USN-4724-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | openldap | 2.4.31-1+nmu2ubuntu8.5+esm7 | USN-7698-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SLES 15 SP1 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SLES 15 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SLES 12 SP5 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SLES 12 SP4 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
Show 24 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SLES 12 SP2 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SLES 12 | openldap2 | 2.4.41-39.1 | SUSE-SU-2021:0692-1 |
| SLES 11 SP4 | openldap2 +1 | 2.4.26-0.74.26.1 | SUSE-SU-2021:14700-1 |
| SLES 11 | openldap2-client-openssl1 | 2.4.26-0.74.26.1 | SUSE-SU-2021:14700-1 |
| SLES for SAP 15 SP1 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SLES for SAP 15 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SLES for SAP 12 SP5 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1, SUSE-SU-2021:0692-1 |
| SLES for SAP 12 SP4 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1, SUSE-SU-2021:0692-1 |
| SLES for SAP 12 SP3 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1, SUSE-SU-2021:0692-1 |
| SLES for SAP 12 SP2 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1, SUSE-SU-2021:0692-1 |
| SLE HPC 15 SP1 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SLE HPC 15 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SUSE OpenStack Cloud Crowbar 9 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SUSE OpenStack Cloud Crowbar 8 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SUSE OpenStack Cloud 9 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SUSE OpenStack Cloud 8 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SUSE OpenStack Cloud 7 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SUSE Manager Server 4.0 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SUSE Manager Retail Branch Server 4.0 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SUSE Manager Proxy 4.0 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | openldap2 +1 | 2.4.26-0.74.26.1 | SUSE-SU-2021:14700-1 |
| SUSE HPE Helion OpenStack 8 | openldap2 | 2.4.41-18.83.1 | SUSE-SU-2021:0693-1 |
| SUSE Enterprise Storage 6 | openldap2 | 2.4.46-9.48.1 | SUSE-SU-2021:0723-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.2 | openldap2 | 2.4.46-lp152.14.18.1 | openSUSE-SU-2021:0408-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | openldap | 2.4.57-r0 | — |
| Alpine v3.23 | openldap | 2.4.57-r0 | — |
| Alpine v3.22 | openldap | 2.4.57-r0 | — |
| Alpine v3.21 | openldap | 2.4.57-r0 | — |
| Alpine v3.20 | openldap | 2.4.57-r0 | — |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | openldap | 2.4.57-r0 | — |
| Alpine v3.18 | openldap | 2.4.57-r0 | — |
| Alpine v3.17 | openldap | 2.4.57-r0 | — |
| Alpine v3.16 | openldap | 2.4.57-r0 | — |
| Alpine v3.15 | openldap | 2.4.57-r0 | — |
| Alpine v3.14 | openldap | 2.4.57-r0 | — |
| Alpine v3.13 | openldap | 2.4.57-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | openldap +4 | 2.4.44-25.amzn2.0.5 | ALAS2-2023-2033 |
Advisories 13
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- USN-7698-1 openldap vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-4724-1 openldap vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-4845-1 openldap - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2544-1 openldap - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2021:0692-1 Security update for openldap2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:0693-1 Security update for openldap2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:0723-1 Security update for openldap2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:14700-1 Security update for openldap2 SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2023-1127 OpenLDAP: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Aug 24, 2025
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- openSUSE-SU-2021:0408-1 Security update for openldap2 SUSE / openSUSE Security Updates · May 7, 2025
- ALAS2-2023-2033 Important: openldap security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · May 2, 2023
References
- https://git.openldap.org/openldap/openldap/-/tags/OPENLDAP_REL_ENG_2_4_57
- https://bugs.openldap.org/show_bug.cgi?id=9428
- https://git.openldap.org/openldap/openldap/-/commit/9d0e8485f3113505743baabf1167e01e4558ccf5
- [debian-lts-announce] 20210203 [SECURITY] [DLA 2544-1] openldap security update mailing-list
- DSA-4845 vendor-advisory
- https://security.netapp.com/advisory/ntap-20210226-0002/
- https://support.apple.com/kb/HT212529
- https://support.apple.com/kb/HT212531
- https://support.apple.com/kb/HT212530
- 20210526 APPLE-SA-2021-05-25-2 macOS Big Sur 11.4 mailing-list
- 20210526 APPLE-SA-2021-05-25-4 Security Update 2021-003 Catalina mailing-list
- 20210526 APPLE-SA-2021-05-25-3 Security Update 2021-004 Mojave mailing-list
- [bookkeeper-issues] 20210628 [GitHub] [bookkeeper] padma81 opened a new issue #2746: Security Vulnerabilities in CentOS 7 image, Upgrade image to CentOS 8 mailing-list
- [bookkeeper-issues] 20210629 [GitHub] [bookkeeper] padma81 opened a new issue #2746: Security Vulnerabilities in CentOS 7 image, Upgrade image to CentOS 8 mailing-list