Description
A flaw was found in tftp-hpa. When the `in.tftpd` remap engine processes an inverse remap rule that also aborts with a non-empty custom error message, it can pass invalid match offsets to the `genmatchstring()` function. This leads to out-of-bounds read/write operations. A remote, unauthenticated attacker can exploit this vulnerability by sending a specially crafted request, causing the daemon to crash and resulting in a denial of service.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Hardened Images | — | — |
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 | tftp-hpa | 5.3+20251116-1 | — |
| Debian 13 | tftp-hpa | No fix yet | — |
| Debian 12 | tftp-hpa | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | tftp-hpa | No fix yet | — |
| Ubuntu 26.04 LTS | tftp-hpa | No fix yet | — |
| Ubuntu 24.04 LTS | tftp-hpa | No fix yet | — |
| Ubuntu 22.04 LTS | tftp-hpa | No fix yet | — |
| Ubuntu 20.04 LTS | tftp-hpa | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | tftp-hpa | No fix yet | — |
| Ubuntu 16.04 LTS | tftp-hpa | No fix yet | — |
| Ubuntu 14.04 LTS | tftp-hpa | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | tftp +1 | 5.2-50.el10_2 | RHSA-2026:98563, RHSA-2026:82280 |
| RHEL 9 | tftp +1 | 5.2-40.el9_8.1 | RHSA-2026:98457, RHSA-2026:80663 |
| RHEL 8 | tftp +1 | 5.2-28.el8_10 | RHSA-2026:78952 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | tftp +1 | 5.2-50.el10_2 | ALSA-2026:82280 |
| AlmaLinux 9 | tftp +1 | 5.2-40.el9_8.1 | ALSA-2026:80663 |
| AlmaLinux 8 | tftp +1 | 5.2-28.el8_10 | ALSA-2026:78952 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | tftp | 5.2-50.el10 | RLSA-2026:98563, RLSA-2026:82280 |
| Rocky Linux 10 | tftp-server | 5.2-51.el10_3 | RLSA-2026:98563 |
| Rocky Linux 9 | tftp | 5.2-40.el9_8.1 | RLSA-2026:98457, RLSA-2026:80663 |
| Rocky Linux 9 | tftp-server | 5.2-41.el9_9 | RLSA-2026:98457 |
| Rocky Linux 8 | tftp | 5.2-28.el8_10 | RLSA-2026:78952 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | tftp | 5.4-1.1 | openSUSE-SU-2026:12412-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | tftp +1 | 5.2-50.el10_2 | ELSA-2026-82280 |
| Oracle Linux 9 | tftp +1 | 5.2-40.el9_8.1 | ELSA-2026-80663 |
| Oracle Linux 8 | tftp +1 | 5.2-28.el8_10 | ELSA-2026-78952 |
Advisories 18
- RHSA-2026:98563 Red Hat Security Advisory: tftp security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:98457 Red Hat Security Advisory: tftp security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RLSA-2026:98563 Moderate: tftp security update Rocky Linux Security Advisories · Nov 13, 2026
- RLSA-2026:98457 Moderate: tftp security update Rocky Linux Security Advisories · Nov 13, 2026
- WID-SEC-2026-3848 Red Hat Enterprise Linux (sssd, tftp, ansible-collection-ansible-posix): Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- openSUSE-SU-2026:12412-1 tftp-5.4-1.1 on GA media SUSE / openSUSE Security Updates · Nov 4, 2026
- ALSA-2026:80663 Moderate: tftp security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:82280 Moderate: tftp security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:78952 Moderate: tftp security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2026:80663 Red Hat Security Advisory: tftp security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2026:82280 Red Hat Security Advisory: tftp security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2026:78952 Red Hat Security Advisory: tftp security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RLSA-2026:82280 Moderate: tftp security update Rocky Linux Security Advisories · Oct 13, 2026
- RLSA-2026:80663 Moderate: tftp security update Rocky Linux Security Advisories · Oct 13, 2026
- ELSA-2026-82280 Moderate: tftp security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Oct 13, 2026
- ELSA-2026-80663 Moderate: tftp security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 11, 2026
- RLSA-2026:78952 Moderate: tftp security update Rocky Linux Security Advisories · Oct 9, 2026
- ELSA-2026-78952 Moderate: tftp security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Oct 8, 2026
References
- RHSA-2026:78952 vendor-advisory
- RHSA-2026:80663 vendor-advisory
- RHSA-2026:82280 vendor-advisory
- RHSA-2026:98457 vendor-advisory
- RHSA-2026:98563 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-85234 vdb-entry
- RHBZ#2460997 issue-tracking
- https://git.kernel.org/pub/scm/network/tftp/tftp-hpa.git/commit/?id=4b493532f5ce052a1c124acd0661233ec7918327