Description
An issue was discovered in MIT Kerberos 5 (aka krb5) through 1.16. The pre-defined function "strlen" is getting a "NULL" string as a parameter value in plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c in the Key Distribution Center (KDC), which allows remote authenticated users to cause a denial of service (NULL pointer dereference) via a modified kadmin client.
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 | krb5 | 1.16.1-1 | — |
| Debian 13 | krb5 | 1.16.1-1 | — |
| Debian 12 | krb5 | 1.16.1-1 | — |
| Debian 9 | krb5 | 1.15-1+deb9u3 | DLA-2771-1 |
| Debian 8 | krb5 | 1.12.1+dfsg-19+deb8u5 | DLA-1643-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | krb5 | 1.16-2ubuntu0.1 | — |
| Ubuntu 16.04 LTS | krb5 | 1.13.2+dfsg-5ubuntu2.1 | — |
| Ubuntu 14.04 LTS | krb5 | 1.12+dfsg-2ubuntu5.4 | — |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | krb5 | 1.15.3-r0 | — |
| Alpine v3.23 | krb5 | 1.15.3-r0 | — |
| Alpine v3.22 | krb5 | 1.15.3-r0 | — |
| Alpine v3.21 | krb5 | 1.15.3-r0 | — |
| Alpine v3.20 | krb5 | 1.15.3-r0 | — |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | krb5 | 1.15.3-r0 | — |
| Alpine v3.18 | krb5 | 1.15.3-r0 | — |
| Alpine v3.17 | krb5 | 1.15.3-r0 | — |
| Alpine v3.16 | krb5 | 1.15.3-r0 | — |
| Alpine v3.15 | krb5 | 1.15.3-r0 | — |
| Alpine v3.14 | krb5 | 1.15.3-r0 | — |
| Alpine v3.13 | krb5 | 1.15.3-r0 | — |
| Alpine v3.12 | krb5 | 1.15.3-r0 | — |
| Alpine v3.11 | krb5 | 1.15.3-r0 | — |
| Alpine v3.10 | krb5 | 1.15.3-r0 | — |
| Alpine v3.9 | krb5 | 1.15.3-r0 | — |
| Alpine v3.8 | krb5 | 1.15.3-r0 | — |
| Alpine v3.7 | krb5 | 1.15.3-r0 | — |
Advisories 2
- DLA-1643-1 krb5 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2771-1 krb5 - security update Debian Security (DSA / DLA) · Mar 9, 2026