CVE-2021-47010 (GCVE-0-2021-47010)

Vulnerability from cvelistv5 – Published: 2024-02-28 08:13 – Updated: 2026-05-11 13:46
VLAI
Title
net: Only allow init netns to set default tcp cong to a restricted algo
Summary
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
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-07-25 15:24 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 992de06308d9a9584d59b96d294ac676f924e437 (git)
Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 9884f745108f7d25b189bbcd6754e284fb29ab68 (git)
Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 6c1ea8bee75df8fe2184a50fcd0f70bf82986f42 (git)
Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < efe1532a6e1a8e3c343d04fff510f0ed80328f9c (git)
Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < e7d7bedd507bb732e600403b7a96f9fe48d0ca31 (git)
Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 8d432592f30fcc34ef5a10aac4887b4897884493 (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.15
Unaffected: 0 , < 4.15 (semver)
Unaffected: 4.19.191 , ≤ 4.19.* (semver)
Unaffected: 5.4.119 , ≤ 5.4.* (semver)
Unaffected: 5.10.37 , ≤ 5.10.* (semver)
Unaffected: 5.11.21 , ≤ 5.11.* (semver)
Unaffected: 5.12.4 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
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linux linux_kernel Affected: 6670e1524477 , < 992de06308d9 (custom)
Affected: 6670e1524477 , < 9884f745108f (custom)
Affected: 6670e1524477 , < 6c1ea8bee75d (custom)
Affected: 6670e1524477 , < efe1532a6e1a (custom)
Affected: 6670e1524477 , < e7d7bedd507b (custom)
Affected: 6670e1524477 , < 8d432592f30f (custom)
Affected: 4.15
Unaffected: 0 , < 4.15 (custom)
Unaffected: 4.19.191 , ≤ 4.20 (custom)
Unaffected: 5.4.119 , ≤ 5.5 (custom)
Unaffected: 5.10.37 , ≤ 5.11 (custom)
Unaffected: 5.11.21 , ≤ 5.12 (custom)
Unaffected: 5.12.4 , ≤ 5.13 (custom)
Unaffected: 5.13 , ≤ * (custom)
    cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*
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    }
  }
}



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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.