Description
An out-of-bounds read and write in NTS client extension field parsing (extens_client_recv) in NTPsec before 1.2.5 allows a remote attacker who can send NTP server-mode replies to an NTS client to corrupt heap memory and crash ntpd, and, combined with the NTS-KE client out-of-bounds read fixed in 1.2.4, to bypass NTS authentication and set the client's time, via an NTS Authenticator and Encrypted Extension Fields field whose nonce length exceeds the field.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| NTPsec | NTPsec | 1.1.4 – < 1.2.5 | 1.2.5 |
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 | ntpsec | 1.2.5+dfsg-1 | — |
| Debian 13 | ntpsec | No fix yet | — |
| Debian 12 | ntpsec | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | ntpsec | No fix yet | — |
| Ubuntu 26.04 LTS | ntpsec | No fix yet | — |
| Ubuntu 24.04 LTS | ntpsec | No fix yet | — |
| Ubuntu 22.04 LTS | ntpsec | No fix yet | — |
| Ubuntu 20.04 LTS | ntpsec | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | ntpsec | No fix yet | — |