Description
An issue was discovered in tls_verify_crl in ProFTPD through 1.3.6b. A dereference of a NULL pointer may occur. This pointer is returned by the OpenSSL sk_X509_REVOKED_value() function when encountering an empty CRL installed by a system administrator. The dereference occurs when validating the certificate of a client connecting to the server in a TLS client/server mutual-authentication setup.
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 | proftpd-dfsg | 1.3.6b-2 | — |
| Debian 13 | proftpd-dfsg | 1.3.6b-2 | — |
| Debian 12 | proftpd-dfsg | 1.3.6b-2 | — |
| Debian 8 | proftpd-dfsg | 1.3.5e+r1.3.5-2+deb8u5 | DLA-2018-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | proftpd-dfsg | No fix yet | — |
| Ubuntu 26.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 25.10 | proftpd-dfsg | No fix yet | — |
| Ubuntu 24.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 22.04 LTS | proftpd-dfsg | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 18.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 16.04 LTS | proftpd-dfsg | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SUSE Package Hub 15 SP1 | proftpd | 1.3.6b-bp151.4.6.2 | openSUSE-SU-2020:0031-1 |
| SUSE Package Hub 15 | proftpd | 1.3.6b-bp151.4.6.2 | openSUSE-SU-2020:0031-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | proftpd | 1.3.6e-1.10 | openSUSE-SU-2024:11196-1 |
| openSUSE Leap 15.1 | proftpd | 1.3.6b-bp151.4.6.2 | openSUSE-SU-2020:0031-1 |
Advisories 3
- DLA-2018-1 proftpd-dfsg - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2020:0031-1 Security update for proftpd SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11196-1 proftpd-1.3.6e-1.10 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- https://github.com/proftpd/proftpd/issues/861
- [debian-lts-announce] 20191130 [SECURITY] [DLA 2018-1] proftpd-dfsg security update mailing-list
- FEDORA-2019-65a983b8b6 vendor-advisory
- FEDORA-2019-bfacf1e958 vendor-advisory
- openSUSE-SU-2020:0031 vendor-advisory
- GLSA-202003-35 vendor-advisory
- https://www.oracle.com/security-alerts/cpuapr2020.html