CVE-2021-47010
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2021
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
net: Only allow init netns to set default tcp cong to a restricted algo
In the Linux kernel, the following vulnerability has been resolved: net: Only allow init netns to set default tcp cong to a restricted algo tcp_set_default_congestion_control() is netns-safe in that it writes to &net->ipv4.tcp_congestion_control, but it also sets ca->flags |= TCP_CONG_NON_RESTRICTED which is not namespaced. This has the unintended side-effect of changing the global net.ipv4.tcp_allowed_congestion_control sysctl, despite the fact that it is read-only: 97684f0970f6 ("net: Make tcp_allowed_congestion_control readonly in non-init netns") Resolve this netns "leak" by only allowing the init netns to set the default algorithm to one that is restricted. This restriction could be removed if tcp_allowed_congestion_control were namespace-ified in the future. This bug was uncovered with https://github.com/JonathonReinhart/linux-netns-sysctl-verify
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 6670e152447732ba90626f36dfc015a13fbf150e | affected | git | 992de06308d9a9584d59b96d294ac676f924e437 | Unavailable | None listed |
| 6670e152447732ba90626f36dfc015a13fbf150e | affected | git | 9884f745108f7d25b189bbcd6754e284fb29ab68 | Unavailable | None listed |
| 6670e152447732ba90626f36dfc015a13fbf150e | affected | git | 6c1ea8bee75df8fe2184a50fcd0f70bf82986f42 | Unavailable | None listed |
| 6670e152447732ba90626f36dfc015a13fbf150e | affected | git | efe1532a6e1a8e3c343d04fff510f0ed80328f9c | Unavailable | None listed |
| 6670e152447732ba90626f36dfc015a13fbf150e | affected | git | e7d7bedd507bb732e600403b7a96f9fe48d0ca31 | Unavailable | None listed |
| 6670e152447732ba90626f36dfc015a13fbf150e | affected | git | 8d432592f30fcc34ef5a10aac4887b4897884493 | Unavailable | None listed |
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
affected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 4.15 | affected | Unavailable | Unavailable | Unavailable | None listed |
| 0 | unaffected | semver | 4.15 | Unavailable | None listed |
| 4.19.191 | unaffected | semver | Unavailable | 4.19.* | None listed |
| 5.4.119 | unaffected | semver | Unavailable | 5.4.* | None listed |
| 5.10.37 | unaffected | semver | Unavailable | 5.10.* | None listed |
| 5.11.21 | unaffected | semver | Unavailable | 5.11.* | None listed |
| 5.12.4 | unaffected | semver | Unavailable | 5.12.* | None listed |
| 5.13 | unaffected | original_commit_for_fix | Unavailable | * | None listed |