CVE-2020-25686

LOWNVD 3.73.7—
EchelonGraph scoreMEDIUM confidence

Score 3.7 from GitHub Security Advisory published 2022-05-24. NVD baseline CVSS 3.7; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
3.7
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 5%CVSS: 3.7Exploit: NoneExposed: 0

A fix is available — apply it.

A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the same name. This flaw allows an off-path attacker on the network to substantially reduce the number of attempts that it would have to perform to forge a reply and have it accepted by dnsmasq. This issue is mentioned in the "Birthday Attacks" section of RFC5452. If chained with CVE-2020-25684, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.

CVSS v3
3.7
EG Score
3.7(medium)
EPSS
91.0%
KEV
Not listed

Published

January 20, 2021

Last Modified

November 4, 2025

References (15)

Patch Availability(11)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatredhat-virtualization-host-0:4.3.13-20210127.0.el7_92021-02-03redhat
redhatredhat-virtualization-host-0:4.4.4-20210201.0.el8_32021-02-03redhat
redhatdnsmasq-0:2.66-14.el7_2.32021-01-25redhat
redhatdnsmasq-0:2.66-21.el7_3.32021-01-25redhat
redhatdnsmasq-0:2.79-6.el8_1.12021-01-19redhat
redhatdnsmasq-0:2.76-16.el7_9.12021-01-19redhat
redhatdnsmasq-0:2.76-2.el7_4.32021-01-19redhat
redhatdnsmasq-0:2.79-13.el8_3.12021-01-19redhat
redhatdnsmasq-0:2.76-7.el7_6.22021-01-19redhat
redhatdnsmasq-0:2.76-10.el7_7.22021-01-19redhat
redhatdnsmasq-0:2.79-11.el8_2.22021-01-19redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(2)

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

All Vendor Advisories

(12)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 11× in last 7d / 44× 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. 2026-07-11 08:25 UTCEPSS rescore
  2. 2026-07-11 08:25 UTCEPSS rescore
  3. 2026-07-09 19:07 UTCEPSS rescore
  4. 2026-07-08 15:12 UTCEPSS rescore
  5. 2026-07-07 13:43 UTCEPSS rescore
  6. 2026-07-07 13:43 UTCEPSS rescore
  7. 2026-07-06 16:25 UTCEPSS rescore
  8. 2026-07-06 16:25 UTCEPSS rescore
  9. 2026-07-06 02:21 UTCEPSS rescore
  10. 2026-07-06 02:21 UTCEPSS rescore
  11. 2026-07-05 02:27 UTCEPSS rescore
  12. 2026-07-04 06:29 UTCEPSS rescore
  13. 2026-07-04 06:28 UTCEPSS rescore
  14. 2026-07-01 15:03 UTCEPSS rescore
  15. 2026-07-01 09:48 UTCOSV refresh
  16. 2026-06-30 23:20 UTCEPSS rescore
  17. 2026-06-30 23:20 UTCEPSS rescore
  18. 2026-06-29 14:04 UTCEPSS rescore
  19. 2026-06-28 14:05 UTCEPSS rescore
  20. 2026-06-28 04:54 UTCEPSS rescore
  21. 2026-06-28 04:54 UTCEPSS rescore
  22. 2026-06-27 03:06 UTCEPSS rescore
  23. 2026-06-25 13:47 UTCEPSS rescore
  24. 2026-06-24 14:03 UTCEPSS rescore
  25. 2026-06-24 14:03 UTCEPSS rescore
Show 55 more
  1. 2026-06-23 21:31 UTCEPSS rescore
  2. 2026-06-23 21:31 UTCEPSS rescore
  3. 2026-06-22 14:23 UTCEPSS rescore
  4. 2026-06-22 14:23 UTCEPSS rescore
  5. 2026-06-21 14:54 UTCEPSS rescore
  6. 2026-06-21 14:54 UTCEPSS rescore
  7. 2026-06-21 01:57 UTCEPSS rescore
  8. 2026-06-21 01:57 UTCEPSS rescore
  9. 2026-06-19 19:23 UTCEPSS rescore
  10. 2026-06-18 17:50 UTCEPSS rescore
  11. 2026-06-17 17:50 UTCEPSS rescore
  12. 2026-06-16 17:50 UTCEPSS rescore
  13. 2026-06-16 17:50 UTCEPSS rescore
  14. 2026-06-15 17:46 UTCEPSS rescore
  15. 2026-06-14 23:15 UTCEPSS rescore
  16. 2026-06-13 22:58 UTCEPSS rescore
  17. 2026-06-13 22:58 UTCEPSS rescore
  18. 2026-06-13 15:43 UTCOSV refresh
  19. 2026-06-12 23:10 UTCEPSS rescore
  20. 2026-06-11 13:58 UTCEPSS rescore
  21. 2026-06-10 22:16 UTCEPSS rescore
  22. 2026-06-10 22:16 UTCEPSS rescore
  23. 2026-06-10 13:20 UTCEPSS rescore
  24. 2026-06-08 14:15 UTCEPSS rescore
  25. 2026-06-08 14:15 UTCEPSS rescore
  26. 2026-06-07 15:23 UTCEPSS rescore
  27. 2026-06-07 15:23 UTCEPSS rescore
  28. 2026-06-06 13:45 UTCEPSS rescore
  29. 2026-06-06 13:45 UTCEPSS rescore
  30. 2026-06-05 22:45 UTCEPSS rescore
  31. 2026-06-05 22:45 UTCEPSS rescore
  32. 2026-06-05 06:08 UTCEPSS rescore
  33. 2026-06-05 06:08 UTCEPSS rescore
  34. 2026-06-04 13:10 UTCEPSS rescore
  35. 2026-06-04 13:10 UTCEPSS rescore
  36. 2026-06-02 20:11 UTCEPSS rescore
  37. 2026-06-02 20:11 UTCEPSS rescore
  38. 2026-06-01 13:50 UTCEPSS rescore
  39. 2026-06-01 13:50 UTCEPSS rescore
  40. 2026-05-31 22:29 UTCEPSS rescore
  41. 2026-05-31 22:29 UTCEPSS rescore
  42. 2026-05-31 00:15 UTCEPSS rescore
  43. 2026-05-31 00:15 UTCEPSS rescore
  44. 2026-05-29 13:42 UTCEPSS rescore
  45. 2026-05-28 13:43 UTCEPSS rescore
  46. 2026-05-28 13:43 UTCEPSS rescore
  47. 2026-05-27 13:39 UTCEPSS rescore
  48. 2026-05-26 21:50 UTCEG score recompute
  49. 2026-05-26 21:50 UTCVendor advisory
  50. 2026-05-26 21:50 UTCGHSA enrichment
  51. 2026-05-26 13:42 UTCEPSS rescore
  52. 2026-05-26 13:42 UTCEPSS rescore
  53. 2026-05-26 07:17 UTCEPSS rescore
  54. 2026-05-26 07:17 UTCEPSS rescore
  55. 2026-05-24 16:48 UTCEPSS rescore

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCknqyf263/dnspooq
    First seen Jan 23, 2021

    DNSpooq - dnsmasq cache poisoning (CVE-2020-25686, CVE-2020-25684, CVE-2020-25685)

    Open source ↗

Frequently asked(5)

What is CVE-2020-25686?
CVE-2020-25686 is a low vulnerability published on January 20, 2021. A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the…
When was CVE-2020-25686 disclosed?
CVE-2020-25686 was first published in the National Vulnerability Database on January 20, 2021, with the most recent update on November 4, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2020-25686 actively exploited?
CVE-2020-25686 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 91.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-25686?
CVE-2020-25686 has a CVSS v3 base score of 3.7 (NVD).
How do I remediate CVE-2020-25686?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-25686, 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.

Dependency Blast Radius

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