
CVE catalog
CVE-2021-26933
xen: CVE-2021-26933
- Severity
- Medium
- Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.33% · Oct 25, 2026
An issue was discovered in Xen 4.9 through 4.14.x. On Arm, a guest is allowed to control whether memory accesses are bypassing the cache. This means that Xen needs to ensure that all writes (such as the ones during scrubbing) have reached the memory before handing over the page to a guest. Unfortunately, the operation to clean the cache is happening before checking if the page was scrubbed. Therefore there is no guarantee when all the writes will reach the memory.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | xen | sid | 4.20.4+39-gf1e1321c87-1 | fixed |
| Debian | xen | forky | 4.20.4+39-gf1e1321c87-1 | fixed |
| Debian | xen | trixie | 4.20.3+127-gc42374a105-0+deb13u1 | fixed |
| Debian | xen | trixie-security | 4.20.4+39-gf1e1321c87-0+deb13u1 | fixed |
| Debian | xen | bookworm | 4.17.5+72-g01140da4e8-1 | fixed |
| Debian | xen | bookworm-security | 4.17.7-0+deb12u1 | fixed |
| Alpine | xen | 3.11 | 4.13.2-r5 | fixed |
| Alpine | xen | 3.12 | 4.13.2-r5 | fixed |
| Alpine | xen | 3.13 | 4.14.1-r2 | fixed |
| Alpine | xen | 3.14 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.15 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.16 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.17 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.18 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.19 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.20 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.21 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.22 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.23 | 4.14.1-r3 | fixed |
| Alpine | xen | 3.24 | 4.14.1-r3 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | xen | source | sid | 4.14.1+11-gb0b734a8b3-1 | not yet assigned | Not reported | Not reported |
| Debian | xen | source | forky | 4.14.1+11-gb0b734a8b3-1 | not yet assigned | Not reported | Not reported |
| Debian | xen | source | trixie | 4.14.1+11-gb0b734a8b3-1 | not yet assigned | Not reported | Not reported |
| Debian | xen | source | bookworm | 4.14.1+11-gb0b734a8b3-1 | not yet assigned | Not reported | Not reported |
| Alpine | xen | apk | 3.11 | 4.13.2-r5 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.12 | 4.13.2-r5 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.13 | 4.14.1-r2 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.14 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.15 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.16 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.17 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.18 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.19 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.20 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.21 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.22 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.23 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
| Alpine | xen | apk | 3.24 | 4.14.1-r3 | Not reported | ALPINE-CVE-2021-26933 | Not reported |
OpenFactory catalog packages
Matching against OpenFactory catalog package versions is in progress.
[Debian 12 (Bookworm)]
- [libxencall1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxen-dev]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxendevicemodel1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxenevtchn1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxenforeignmemory1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxengnttab1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxenhypfs1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxenmisc4.17]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxenstore4]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxentoolcore1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [libxentoollog1]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-doc]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-hypervisor-4.17-amd64]Unknown
Source package: [xen]
Details (2)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-hypervisor-4.17-amd64-dbg]Unknown
Source package: [xen]
Details (2)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-hypervisor-4.17-arm64]Unknown
Source package: [xen]
Details (2)
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-hypervisor-4.17-arm64-dbg]Unknown
Source package: [xen]
Details (2)
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-hypervisor-common]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xenstore-utils]Unknown
Source package: [xen]
Details (4)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-system-amd64]Unknown
Source package: [xen]
Details (2)
4.17.5+72-g01140da4e8-1· amd64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· amd64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
- [xen-system-arm64]Unknown
Source package: [xen]
Details (2)
4.17.5+72-g01140da4e8-1· arm64 · bookwormFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
4.17.5+72-g01140da4e8-1· arm64 · bookworm-securityFixed · Fixed:
4.14.1+11-gb0b734a8b3-1dsa · xen · debian · bookworm; dsa · xen · debian · 12
Observed: