7.8

CVE-2021-47010: linux Uncontrolled Resource Consumption

CVSS: 7.8v3.1HighAnalyzed
AliasesUBUNTU-CVE-2021-47010DEBIAN-CVE-2021-47010
Published 28-02-2024Last modified 11-05-2026
Open JSON

Vulnerability summary

CVE-2021-47010 is a high (CVSS 7.8) Uncontrolled Resource Consumption vulnerability in linux. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16.3% of scored vulnerabilities.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.26%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 28-02-2024
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

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

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.26%

Chance of exploitation in the next 30 days

Percentile

16%

Versus all other CVEs

30-day change

0.00 pp

From 0.26% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.26%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu85 products
  • linux< 4.15.0-151.157 | < 5.4.0-77.86
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 4.15.0-1109.116 | < 5.4.0-1051.53
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 6670e152447732ba90626f36dfc015a13fbf150e, < 992de06308d9a9584d59b96d294ac676f924e437 | ≥ 6670e152447732ba90626f36dfc015a13fbf150e, < 9884f745108f7d25b189bbcd6754e284fb29ab68 | ≥ 6670e152447732ba90626f36dfc015a13fbf150e, < 6c1ea8bee75df8fe2184a50fcd0f70bf82986f42 | ≥ 6670e152447732ba90626f36dfc015a13fbf150e, < efe1532a6e1a8e3c343d04fff510f0ed80328f9c | ≥ 6670e152447732ba90626f36dfc015a13fbf150e, < e7d7bedd507bb732e600403b7a96f9fe48d0ca31 | ≥ 6670e152447732ba90626f36dfc015a13fbf150e, < 8d432592f30fcc34ef5a10aac4887b4897884493 | 4.15
  • linux_kernel≥ 4.15, < 4.19.191 | ≥ 4.20, < 5.4.119 | ≥ 5.5, < 5.10.37 | ≥ 5.11, < 5.11.21 | ≥ 5.12, < 5.12.4
Debian1 product
  • linux< 5.10.38-1

3 vendors · 88 products

References

10 links