CVE-2020-11091

MEDIUMNVD 5.85.8—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.8 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 63% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
5.8
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 1%CVSS: 5.8Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In Weave Net before version 2.6.3, an attacker able to run a process as root in a container is able to respond to DNS requests from the host and thereby insert themselves as a fake service. In a cluster with an IPv4 internal network, if IPv6 is not totally disabled on the host (via ipv6.disable=1 on the kernel cmdline), it will be either unconfigured or configured on some interfaces, but it's pretty likely that ipv6 forwarding is disabled, ie /proc/sys/net/ipv6/conf//forwarding == 0. Also by default, /proc/sys/net/ipv6/conf//accept_ra == 1. The combination of these 2 sysctls means that the host accepts router advertisements and configure the IPv6 stack using them. By sending rogue router advertisements, an attacker can reconfigure the host to redirect part or all of the IPv6 traffic of the host to the attacker controlled container. Even if there was no IPv6 traffic before, if the DNS returns A (IPv4) and AAAA (IPv6) records, many HTTP libraries will try to connect via IPv6 first then fallback to IPv4, giving an opportunity to the attacker to respond. If by chance you also have on the host a vulnerability like last year's RCE in apt (CVE-2019-3462), you can now escalate to the host. Weave Net version 2.6.3 disables the accept_ra option on the veth devices that it creates.

CVSS v3
5.8
EG Score
5.8(medium)
EPSS
54.7%
KEV
Not listed

Published

June 3, 2020

Last Modified

November 21, 2024

References (4)

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFixed inDependents
github.com/weaveworks/weave—2.6.3+incompatible—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 12× in last 7d / 41× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-22 14:05 UTCEPSS rescore
  2. 2026-07-21 15:22 UTCEPSS rescore
  3. 2026-07-21 15:22 UTCEPSS rescore
  4. 2026-07-20 17:04 UTCEPSS rescore
  5. 2026-07-19 14:28 UTCEPSS rescore
  6. 2026-07-19 14:28 UTCEPSS rescore
  7. 2026-07-19 11:52 UTCOSV refresh
  8. 2026-07-19 02:26 UTCEPSS rescore
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  10. 2026-07-18 10:02 UTCEPSS rescore
  11. 2026-07-16 16:59 UTCEPSS rescore
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  13. 2026-07-15 16:55 UTCEPSS rescore
  14. 2026-07-13 22:27 UTCEPSS rescore
  15. 2026-07-13 06:10 UTCEPSS rescore
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  17. 2026-07-12 05:44 UTCEPSS rescore
  18. 2026-07-11 08:24 UTCEPSS rescore
  19. 2026-07-09 19:06 UTCEPSS rescore
  20. 2026-07-08 15:11 UTCEPSS rescore
  21. 2026-07-07 13:43 UTCEPSS rescore
  22. 2026-07-06 16:25 UTCEPSS rescore
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  24. 2026-07-06 02:20 UTCEPSS rescore
  25. 2026-07-05 02:27 UTCEPSS rescore
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  1. 2026-07-04 06:28 UTCEPSS rescore
  2. 2026-07-01 19:31 UTCOSV refresh
  3. 2026-07-01 15:03 UTCEPSS rescore
  4. 2026-07-01 15:03 UTCEPSS rescore
  5. 2026-06-29 14:04 UTCEPSS rescore
  6. 2026-06-29 14:04 UTCEPSS rescore
  7. 2026-06-28 14:05 UTCEPSS rescore
  8. 2026-06-28 04:54 UTCEPSS rescore
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  10. 2026-06-27 03:06 UTCEPSS rescore
  11. 2026-06-25 13:47 UTCEPSS rescore
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  13. 2026-06-24 14:03 UTCEPSS rescore
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  15. 2026-06-23 21:31 UTCEPSS rescore
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  17. 2026-06-22 14:23 UTCEPSS rescore
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  19. 2026-06-21 14:54 UTCEPSS rescore
  20. 2026-06-21 14:54 UTCEPSS rescore
  21. 2026-06-21 01:57 UTCEPSS rescore
  22. 2026-06-21 01:57 UTCEPSS rescore
  23. 2026-06-19 19:23 UTCEPSS rescore
  24. 2026-06-19 19:23 UTCEPSS rescore
  25. 2026-06-18 17:50 UTCEPSS rescore
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  27. 2026-06-17 17:50 UTCEPSS rescore
  28. 2026-06-17 17:50 UTCEPSS rescore
  29. 2026-06-16 17:50 UTCEPSS rescore
  30. 2026-06-16 17:50 UTCEPSS rescore
  31. 2026-06-15 17:46 UTCEPSS rescore
  32. 2026-06-14 23:15 UTCEPSS rescore
  33. 2026-06-14 23:15 UTCEPSS rescore
  34. 2026-06-14 01:43 UTCOSV refresh
  35. 2026-06-13 22:58 UTCEPSS rescore
  36. 2026-06-13 22:58 UTCEPSS rescore
  37. 2026-06-12 23:09 UTCEPSS rescore
  38. 2026-06-11 13:58 UTCEPSS rescore
  39. 2026-06-10 22:16 UTCEPSS rescore
  40. 2026-06-10 22:16 UTCEPSS rescore
  41. 2026-06-10 13:20 UTCEPSS rescore
  42. 2026-06-08 14:15 UTCEPSS rescore
  43. 2026-06-08 14:15 UTCEPSS rescore
  44. 2026-06-07 15:23 UTCEPSS rescore
  45. 2026-06-07 15:23 UTCEPSS rescore
  46. 2026-06-06 13:45 UTCEPSS rescore
  47. 2026-06-06 13:45 UTCEPSS rescore
  48. 2026-06-06 13:45 UTCEPSS rescore
  49. 2026-06-05 22:45 UTCEPSS rescore
  50. 2026-06-05 22:45 UTCEPSS rescore
  51. 2026-06-05 06:08 UTCEPSS rescore
  52. 2026-06-04 13:10 UTCEPSS rescore
  53. 2026-06-04 13:10 UTCEPSS rescore
  54. 2026-06-02 20:11 UTCEPSS rescore
  55. 2026-06-02 20:11 UTCEPSS rescore
  56. 2026-06-01 13:50 UTCEPSS rescore
  57. 2026-05-31 22:29 UTCEPSS rescore
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  59. 2026-05-31 00:15 UTCEPSS rescore
  60. 2026-05-31 00:14 UTCEPSS rescore
  61. 2026-05-29 13:42 UTCEPSS rescore
  62. 2026-05-29 13:42 UTCEPSS rescore
  63. 2026-05-28 13:43 UTCEPSS rescore
  64. 2026-05-28 13:43 UTCEPSS rescore
  65. 2026-05-27 13:39 UTCEPSS rescore
  66. 2026-05-27 03:01 UTCEG score recompute
  67. 2026-05-26 13:42 UTCEPSS rescore
  68. 2026-05-26 13:42 UTCEPSS rescore
  69. 2026-05-26 07:17 UTCEPSS rescore
  70. 2026-05-26 07:17 UTCEPSS rescore
  71. 2026-05-23 04:04 UTCOSV refresh

Frequently asked(5)

What is CVE-2020-11091?
CVE-2020-11091 is a medium vulnerability published on June 3, 2020. In Weave Net before version 2.6.3, an attacker able to run a process as root in a container is able to respond to DNS requests from the host and thereby insert themselves as a fake service. In a cluster with an IPv4 internal network, if IPv6 is not totally disabled on the host (via ipv6.disable=1…
When was CVE-2020-11091 disclosed?
CVE-2020-11091 was first published in the National Vulnerability Database on June 3, 2020, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2020-11091 actively exploited?
CVE-2020-11091 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 54.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-11091?
CVE-2020-11091 has a CVSS v3 base score of 5.8 (NVD).
How do I remediate CVE-2020-11091?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-11091, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

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