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
Elevated
8.9EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 81%
CISA-KEV: Not listedEPSS PROB: 81%CVSS: 8.1Exploit: Elevated riskExposed: 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 PROB
81%
EPSS %ILE
100%
KEV
Not listed

Published

January 20, 2021

Last Modified

November 4, 2025

Advisory Details (6)

Auto-updated Sep 9, 2026
Patch available. Sources: redhat.
generic

[SECURITY] Fedora 32 Update: dnsmasq-2.84-1.fc32 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/
generic Patch Available

[SECURITY] [DLA 2604-1] dnsmasq security update

https://lists.debian.org/debian-lts-announce/2021/03/msg00027.html
redhat Patch Available

1881875 – (CVE-2020-25681) CVE-2020-25681 dnsmasq: heap-based buffer overflow in sort_rrset() when DNSSEC is enabled

Affected: Red Hat Enterprise Linux 5, 6, and 7 as they are not compiled with DNSSEC support.

https://bugzilla.redhat.com/show_bug.cgi?id=1881875
generic

[SECURITY] [DSA 4844-1] dnsmasq security update

https://www.debian.org/security/2021/dsa-4844
generic

Dnsmasq: Multiple vulnerabilities (GLSA 202101-17) — Gentoo security

https://security.gentoo.org/glsa/202101-17
generic

[SECURITY] Fedora 33 Update: dnsmasq-2.83-1.fc33 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/

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.

Affected Packages

(21 across 21 ecosystems)
Alpine:v3.10(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.11(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.12(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.13(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.14(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.15(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.16(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.17(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.18(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.19(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.20(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.21(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.22(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-r0—
Debian:10(1)
PackageVulnerable rangeFixed inDependents
dnsmasq2.80-12.80-1+deb10u1—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
dnsmasq—2.83-1—
Debian:9(1)
PackageVulnerable rangeFixed inDependents
dnsmasq2.76-5, 2.76-5+deb9u1, 2.76-5+deb9u22.76-5+deb9u3—

Weakness Classification(1)

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

All Vendor Advisories

(5)

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 5× in last 7d / 14× 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. 2026-09-18 19:23 UTCEPSS rescore
  2. 2026-09-17 19:22 UTCEPSS rescore
  3. 2026-09-17 19:22 UTCEPSS rescore
  4. 2026-09-16 14:04 UTCEPSS rescore
  5. 2026-09-13 16:42 UTCEPSS rescore
  6. 2026-09-12 14:56 UTCEPSS rescore
  7. 2026-09-10 09:29 UTCEPSS rescore
  8. 2026-09-06 23:31 UTCOSV refresh
  9. 2026-09-06 13:44 UTCEPSS rescore
  10. 2026-09-05 15:24 UTCEPSS rescore
  11. 2026-09-02 14:08 UTCEPSS rescore
  12. 2026-08-30 19:14 UTCEPSS rescore
  13. 2026-08-26 14:42 UTCEPSS rescore
  14. 2026-08-25 13:45 UTCEPSS rescore
  15. 2026-08-20 09:31 UTCOSV refresh
  16. 2026-08-19 17:00 UTCEPSS rescore
  17. 2026-08-16 02:11 UTCEPSS rescore
  18. 2026-08-15 01:26 UTCEPSS rescore
  19. 2026-08-12 13:47 UTCEPSS rescore
  20. 2026-08-09 13:43 UTCEPSS rescore
  21. 2026-08-08 16:33 UTCEPSS rescore
  22. 2026-08-07 16:23 UTCEPSS rescore
  23. 2026-08-05 04:41 UTCOSV refresh
  24. 2026-08-04 10:34 UTCEPSS rescore
  25. 2026-08-02 02:23 UTCEPSS rescore
Show 66 more
  1. 2026-07-30 16:25 UTCEPSS rescore
  2. 2026-07-26 14:51 UTCEPSS rescore
  3. 2026-07-25 14:15 UTCEPSS rescore
  4. 2026-07-25 14:14 UTCEPSS rescore
  5. 2026-07-24 14:14 UTCEPSS rescore
  6. 2026-07-23 01:51 UTCEG score recompute▲ 0.80
  7. 2026-07-22 22:37 UTCEG score recompute
  8. 2026-07-22 14:05 UTCEPSS rescore
  9. 2026-07-21 15:22 UTCEPSS rescore
  10. 2026-07-21 15:22 UTCEPSS rescore
  11. 2026-07-20 17:04 UTCEPSS rescore
  12. 2026-07-20 17:04 UTCEPSS rescore
  13. 2026-07-19 02:52 UTCOSV refresh
  14. 2026-07-16 16:59 UTCEPSS rescore
  15. 2026-07-15 16:55 UTCEPSS rescore
  16. 2026-07-13 22:27 UTCEPSS rescore
  17. 2026-07-13 22:27 UTCEPSS rescore
  18. 2026-07-09 19:07 UTCEPSS rescore
  19. 2026-07-08 15:12 UTCEPSS rescore
  20. 2026-07-04 06:29 UTCEPSS rescore
  21. 2026-07-04 06:28 UTCEPSS rescore
  22. 2026-07-01 15:03 UTCEPSS rescore
  23. 2026-07-01 09:48 UTCOSV refresh
  24. 2026-06-28 14:05 UTCEPSS rescore
  25. 2026-06-27 03:06 UTCEPSS rescore
  26. 2026-06-25 13:47 UTCEPSS rescore
  27. 2026-06-23 21:31 UTCEPSS rescore
  28. 2026-06-23 21:31 UTCEPSS rescore
  29. 2026-06-21 01:57 UTCEPSS rescore
  30. 2026-06-21 01:57 UTCEPSS rescore
  31. 2026-06-17 17:50 UTCEPSS rescore
  32. 2026-06-15 17:46 UTCEPSS rescore
  33. 2026-06-14 23:15 UTCEPSS rescore
  34. 2026-06-13 15:43 UTCOSV refresh
  35. 2026-06-12 23:10 UTCEPSS rescore
  36. 2026-06-11 13:58 UTCEPSS rescore
  37. 2026-06-10 22:16 UTCEPSS rescore
  38. 2026-06-10 22:16 UTCEPSS rescore
  39. 2026-06-10 13:20 UTCEPSS rescore
  40. 2026-06-08 14:15 UTCEPSS rescore
  41. 2026-06-08 14:15 UTCEPSS rescore
  42. 2026-06-06 13:45 UTCEPSS rescore
  43. 2026-06-06 13:45 UTCEPSS rescore
  44. 2026-06-05 22:45 UTCEPSS rescore
  45. 2026-06-05 22:45 UTCEPSS rescore
  46. 2026-06-05 06:08 UTCEPSS rescore
  47. 2026-06-05 06:08 UTCEPSS rescore
  48. 2026-06-04 13:10 UTCEPSS rescore
  49. 2026-06-04 13:10 UTCEPSS rescore
  50. 2026-06-02 20:11 UTCEPSS rescore
  51. 2026-06-02 20:11 UTCEPSS rescore
  52. 2026-06-01 13:50 UTCEPSS rescore
  53. 2026-06-01 13:50 UTCEPSS rescore
  54. 2026-05-31 22:29 UTCEPSS rescore
  55. 2026-05-31 22:29 UTCEPSS rescore
  56. 2026-05-31 00:15 UTCEPSS rescore
  57. 2026-05-31 00:15 UTCEPSS rescore
  58. 2026-05-29 13:42 UTCEPSS rescore
  59. 2026-05-28 13:43 UTCEPSS rescore
  60. 2026-05-28 13:43 UTCEPSS rescore
  61. 2026-05-27 13:39 UTCEPSS rescore
  62. 2026-05-26 21:50 UTCEG score recompute
  63. 2026-05-26 21:50 UTCVendor advisory
  64. 2026-05-26 21:50 UTCGHSA enrichment
  65. 2026-05-26 07:17 UTCEPSS rescore
  66. 2026-05-26 07:17 UTCEPSS rescore

Related CVEs(same vendor + same CWE)

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 81% probability of exploitation in the next 30 days, which ranks it in the top 0.4% of all scored CVEs.
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.

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