CVE-2020-25681

HIGHNVD 8.18.9
EchelonGraph scoreHIGH confidence

Score elevated to 8.9 because EPSS predicts 81% probability of exploitation within the next 30 days (top 0.4% of all CVEs). NVD baseline CVSS 8.1 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction ≥85%
Sources: epss, ghsa, nvd
Trending — 3 sources updated this weekElevated
8.1
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 81%
CISA-KEV: Not listedEPSS: 81%CVSS: 8.1Exploit: NoneExposed: 0

A fix is available — apply it.

A flaw was found in dnsmasq before version 2.83. A heap-based buffer overflow was discovered in the way RRSets are sorted before validating with DNSSEC data. An attacker on the network, who can forge DNS replies such as that they are accepted as valid, could use this flaw to cause a buffer overflow with arbitrary data in a heap memory segment, possibly executing code on the machine. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

CVSS v3
8.1
EG Score
8.9(high)
EG Risk
77(Track)
EG Risk 77/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity89% × 45%
Exploitation81% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
99.6%
KEV
Not listed

Published

January 20, 2021

Last Modified

November 4, 2025

Patch Availability(4)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntudnsmasq-utils (2.75-1ubuntu0.16.04.7) @ xenial2026-05-26ubuntu
redhatdnsmasq-0:2.79-13.el8_3.12021-01-19redhat
redhatdnsmasq-0:2.79-6.el8_1.12021-01-19redhat
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(1)

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

All Vendor Advisories

(5)

Data Freshness Timeline

(refreshed 9× in last 7d / 23× 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. 2026-07-23 01:51 UTCEG score recompute 0.80
  2. 2026-07-22 22:37 UTCEG score recompute
  3. 2026-07-22 14:05 UTCEPSS rescore
  4. 2026-07-21 15:22 UTCEPSS rescore
  5. 2026-07-21 15:22 UTCEPSS rescore
  6. 2026-07-20 17:04 UTCEPSS rescore
  7. 2026-07-20 17:04 UTCEPSS rescore
  8. 2026-07-19 02:52 UTCOSV refresh
  9. 2026-07-16 16:59 UTCEPSS rescore
  10. 2026-07-15 16:55 UTCEPSS rescore
  11. 2026-07-13 22:27 UTCEPSS rescore
  12. 2026-07-13 22:27 UTCEPSS rescore
  13. 2026-07-09 19:07 UTCEPSS rescore
  14. 2026-07-08 15:12 UTCEPSS rescore
  15. 2026-07-04 06:29 UTCEPSS rescore
  16. 2026-07-04 06:28 UTCEPSS rescore
  17. 2026-07-01 15:03 UTCEPSS rescore
  18. 2026-07-01 09:48 UTCOSV refresh
  19. 2026-06-28 14:05 UTCEPSS rescore
  20. 2026-06-27 03:06 UTCEPSS rescore
  21. 2026-06-25 13:47 UTCEPSS rescore
  22. 2026-06-23 21:31 UTCEPSS rescore
  23. 2026-06-23 21:31 UTCEPSS rescore
  24. 2026-06-21 01:57 UTCEPSS rescore
  25. 2026-06-21 01:57 UTCEPSS rescore
Show 36 more
  1. 2026-06-17 17:50 UTCEPSS rescore
  2. 2026-06-15 17:46 UTCEPSS rescore
  3. 2026-06-14 23:15 UTCEPSS rescore
  4. 2026-06-13 15:43 UTCOSV refresh
  5. 2026-06-12 23:10 UTCEPSS rescore
  6. 2026-06-11 13:58 UTCEPSS rescore
  7. 2026-06-10 22:16 UTCEPSS rescore
  8. 2026-06-10 22:16 UTCEPSS rescore
  9. 2026-06-10 13:20 UTCEPSS rescore
  10. 2026-06-08 14:15 UTCEPSS rescore
  11. 2026-06-08 14:15 UTCEPSS rescore
  12. 2026-06-06 13:45 UTCEPSS rescore
  13. 2026-06-06 13:45 UTCEPSS rescore
  14. 2026-06-05 22:45 UTCEPSS rescore
  15. 2026-06-05 22:45 UTCEPSS rescore
  16. 2026-06-05 06:08 UTCEPSS rescore
  17. 2026-06-05 06:08 UTCEPSS rescore
  18. 2026-06-04 13:10 UTCEPSS rescore
  19. 2026-06-04 13:10 UTCEPSS rescore
  20. 2026-06-02 20:11 UTCEPSS rescore
  21. 2026-06-02 20:11 UTCEPSS rescore
  22. 2026-06-01 13:50 UTCEPSS rescore
  23. 2026-06-01 13:50 UTCEPSS rescore
  24. 2026-05-31 22:29 UTCEPSS rescore
  25. 2026-05-31 22:29 UTCEPSS rescore
  26. 2026-05-31 00:15 UTCEPSS rescore
  27. 2026-05-31 00:15 UTCEPSS rescore
  28. 2026-05-29 13:42 UTCEPSS rescore
  29. 2026-05-28 13:43 UTCEPSS rescore
  30. 2026-05-28 13:43 UTCEPSS rescore
  31. 2026-05-27 13:39 UTCEPSS rescore
  32. 2026-05-26 21:50 UTCEG score recompute
  33. 2026-05-26 21:50 UTCVendor advisory
  34. 2026-05-26 21:50 UTCGHSA enrichment
  35. 2026-05-26 07:17 UTCEPSS rescore
  36. 2026-05-26 07:17 UTCEPSS rescore

Frequently asked(5)

What is CVE-2020-25681?
CVE-2020-25681 is a high vulnerability published on January 20, 2021. A flaw was found in dnsmasq before version 2.83. A heap-based buffer overflow was discovered in the way RRSets are sorted before validating with DNSSEC data. An attacker on the network, who can forge DNS replies such as that they are accepted as valid, could use this flaw to cause a buffer overflow…
When was CVE-2020-25681 disclosed?
CVE-2020-25681 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-2020-25681 actively exploited?
CVE-2020-25681 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-25681?
CVE-2020-25681 has a CVSS v3 base score of 8.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 8.9.
How do I remediate CVE-2020-25681?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-25681, 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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