Description
An issue was discovered in Xen 4.6 through 4.14.x. When acting upon a guest XS_RESET_WATCHES request, not all tracking information is freed. A guest can cause unbounded memory usage in oxenstored. This can lead to a system-wide DoS. Only systems using the Ocaml Xenstored implementation are vulnerable. Systems using the C Xenstored implementation are not vulnerable.
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 | xen | 4.14.0+88-g1d1d1f5391-1 | — |
| Debian 13 | xen | 4.14.0+88-g1d1d1f5391-1 | — |
| Debian 12 | xen | 4.14.0+88-g1d1d1f5391-1 | — |
| Debian 10 | xen | 4.11.4+57-g41a822c392-2 | DSA-4812-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | xen | No fix yet | — |
| Ubuntu 18.04 LTS | xen | No fix yet | — |
| Ubuntu 16.04 LTS | xen | No fix yet | — |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | xen | 4.14.1-r0 | — |
| Alpine v3.23 | xen | 4.14.1-r0 | — |
| Alpine v3.22 | xen | 4.14.1-r0 | — |
| Alpine v3.21 | xen | 4.14.1-r0 | — |
| Alpine v3.20 | xen | 4.14.1-r0 | — |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | xen | 4.14.1-r0 | — |
| Alpine v3.18 | xen | 4.14.1-r0 | — |
| Alpine v3.17 | xen | 4.14.1-r0 | — |
| Alpine v3.16 | xen | 4.14.1-r0 | — |
| Alpine v3.15 | xen | 4.14.1-r0 | — |
| Alpine v3.14 | xen | 4.14.1-r0 | — |
| Alpine v3.13 | xen | 4.14.1-r0 | — |
| Alpine v3.12 | xen | 4.13.2-r3 | — |
| Alpine v3.11 | xen | 4.13.2-r3 | — |
Advisories 1
- DSA-4812-1 xen - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- https://xenbits.xenproject.org/xsa/advisory-330.txt
- DSA-4812 vendor-advisory
- FEDORA-2020-64859a826b vendor-advisory
- FEDORA-2020-df772b417b vendor-advisory