CVE-2020-35730

CRITICALNVD 6.19.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2023-06-22), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 6.1 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 4 sources updated this weekExploited in the wild
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 33%CVSS: 6.1Exploit: cisa kev · ssvc active · epss top5pctExposed services: Not assessed

A fix is available — apply it.

An XSS issue was discovered in Roundcube Webmail before 1.2.13, 1.3.x before 1.3.16, and 1.4.x before 1.4.10. The attacker can send a plain text e-mail message, with JavaScript in a link reference element that is mishandled by linkref_addindex in rcube_string_replacer.php.

CVSS v3
6.1
EG Score
9.0CRITICALhigh confidence
EG Risk
81
EG Risk 81/100CISA SSVC

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
Severity90% × 45%
Exploitation100% × 40%
Automatability0% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
33%
EPSS %ILE
98th
KEV
⚠ Exploited

CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation active (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

December 28, 2020

Last Modified

November 4, 2025

Advisory Details (8)

Auto-updated Jun 13, 2026
Patch available. Sources: github_release.
generic Patch Available

#978491 - roundcube: CVE-2020-35730: XSS vulnerability via malious HTML or plaintext messages - Debian Bug report logs

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=978491
generic

Roundcube Webmail Downloads

https://roundcube.net/download/
generic

[SECURITY] Fedora 32 Update: roundcubemail-1.4.10-1.fc32 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HMLIZWKMTRCLU7KZLEQHELS4INXJ7X5Q/
generic

[SECURITY] Fedora 33 Update: roundcubemail-1.4.10-1.fc33 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HCEU4BM5WGIDJWP6Z4PCH62ZMH57QYM2/
github_release Patch Available

Roundcube Webmail 1.4.10

Patch available: roundcube/roundcubemail 1.4.10

https://github.com/roundcube/roundcubemail/releases/tag/1.4.10
github_release Patch Available

Roundcube Webmail 1.3.16

Patch available: roundcube/roundcubemail 1.3.16

https://github.com/roundcube/roundcubemail/releases/tag/1.3.16
github_release Patch Available

Roundcube Webmail 1.2.13

Patch available: roundcube/roundcubemail 1.2.13

https://github.com/roundcube/roundcubemail/releases/tag/1.2.13
generic

Comparing 1.4.9...1.4.10 · roundcube/roundcubemail · GitHub

https://github.com/roundcube/roundcubemail/compare/1.4.9...1.4.10

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubunturoundcube-sqlite3 (1.3.6+dfsg.1-1ubuntu0.1~esm2) @ bionic2026-10-05ubuntu

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

(6 across 6 ecosystems)
Debian:10(1)
PackageVulnerable rangeFix by version rangeDependents
roundcube1.3.10+dfsg.1-1 ... 1.3.8+dfsg.1-2 (7 versions)
  • every version up to 1.3.16+dfsg.1-1~deb10u1: fixed in 1.3.16+dfsg.1-1~deb10u1
—
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
roundcube—
  • every version up to 1.4.10+dfsg.1-1: fixed in 1.4.10+dfsg.1-1
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
roundcube—
  • every version up to 1.4.10+dfsg.1-1: fixed in 1.4.10+dfsg.1-1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
roundcube—
  • every version up to 1.4.10+dfsg.1-1: fixed in 1.4.10+dfsg.1-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
roundcube—
  • every version up to 1.4.10+dfsg.1-1: fixed in 1.4.10+dfsg.1-1
—
Debian:9(1)
PackageVulnerable rangeFix by version rangeDependents
roundcube1.2.3+dfsg.1-4 ... 1.2.3+dfsg.1-4+deb9u7 (8 versions)
  • every version up to 1.2.3+dfsg.1-4+deb9u8: fixed in 1.2.3+dfsg.1-4+deb9u8
—

Weakness Classification(1)

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

All Vendor Advisories

(1)

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 86× in last 7d / 382× 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.

Showing the most recent 100 of 1,508 total refreshes for this CVE.

  1. 2026-10-05 19:11 UTCVendor advisory
  2. 2026-10-05 19:10 UTCGHSA enrichment
  3. 2026-10-05 15:00 UTCGHSA enrichment
  4. 2026-10-05 10:49 UTCVendor advisory
  5. 2026-10-05 10:49 UTCGHSA enrichment
  6. 2026-10-05 06:38 UTCVendor advisory
  7. 2026-10-05 06:38 UTCGHSA enrichment
  8. 2026-10-05 02:28 UTCEG score recompute
  9. 2026-10-05 02:28 UTCVendor advisory
  10. 2026-10-05 02:28 UTCGHSA enrichment
  11. 2026-10-04 23:18 UTCEPSS rescore
  12. 2026-10-04 22:18 UTCVendor advisory
  13. 2026-10-04 22:18 UTCGHSA enrichment
  14. 2026-10-04 18:08 UTCVendor advisory
  15. 2026-10-04 18:08 UTCGHSA enrichment
  16. 2026-10-04 13:59 UTCVendor advisory
  17. 2026-10-04 13:59 UTCGHSA enrichment
  18. 2026-10-04 09:49 UTCVendor advisory
  19. 2026-10-04 09:49 UTCGHSA enrichment
  20. 2026-10-04 05:39 UTCVendor advisory
  21. 2026-10-04 05:39 UTCGHSA enrichment
  22. 2026-10-04 01:29 UTCGHSA enrichment
  23. 2026-10-03 21:16 UTCVendor advisory
  24. 2026-10-03 21:16 UTCGHSA enrichment
  25. 2026-10-03 17:06 UTCEG score recompute
Show 75 more
  1. 2026-10-03 17:06 UTCVendor advisory
  2. 2026-10-03 17:06 UTCGHSA enrichment
  3. 2026-10-03 14:22 UTCEPSS rescore
  4. 2026-10-03 12:55 UTCVendor advisory
  5. 2026-10-03 12:55 UTCGHSA enrichment
  6. 2026-10-03 08:44 UTCGHSA enrichment
  7. 2026-10-03 04:33 UTCVendor advisory
  8. 2026-10-03 04:33 UTCGHSA enrichment
  9. 2026-10-03 00:23 UTCVendor advisory
  10. 2026-10-03 00:23 UTCGHSA enrichment
  11. 2026-10-02 20:13 UTCEG score recompute
  12. 2026-10-02 20:13 UTCVendor advisory
  13. 2026-10-02 20:13 UTCGHSA enrichment
  14. 2026-10-02 16:00 UTCVendor advisory
  15. 2026-10-02 16:00 UTCGHSA enrichment
  16. 2026-10-02 11:49 UTCGHSA enrichment
  17. 2026-10-02 07:37 UTCVendor advisory
  18. 2026-10-02 07:37 UTCGHSA enrichment
  19. 2026-10-02 03:27 UTCVendor advisory
  20. 2026-10-02 03:27 UTCGHSA enrichment
  21. 2026-10-01 23:17 UTCEG score recompute
  22. 2026-10-01 23:17 UTCGHSA enrichment
  23. 2026-10-01 19:07 UTCVendor advisory
  24. 2026-10-01 19:07 UTCGHSA enrichment
  25. 2026-10-01 14:56 UTCVendor advisory
  26. 2026-10-01 14:56 UTCGHSA enrichment
  27. 2026-10-01 10:46 UTCVendor advisory
  28. 2026-10-01 10:46 UTCGHSA enrichment
  29. 2026-10-01 06:36 UTCVendor advisory
  30. 2026-10-01 06:36 UTCGHSA enrichment
  31. 2026-10-01 02:26 UTCVendor advisory
  32. 2026-10-01 02:26 UTCGHSA enrichment
  33. 2026-09-30 22:16 UTCVendor advisory
  34. 2026-09-30 22:16 UTCGHSA enrichment
  35. 2026-09-30 18:06 UTCEG score recompute
  36. 2026-09-30 18:06 UTCVendor advisory
  37. 2026-09-30 18:06 UTCGHSA enrichment
  38. 2026-09-30 14:59 UTCEPSS rescore
  39. 2026-09-30 13:57 UTCVendor advisory
  40. 2026-09-30 13:56 UTCGHSA enrichment
  41. 2026-09-30 09:46 UTCVendor advisory
  42. 2026-09-30 09:46 UTCGHSA enrichment
  43. 2026-09-30 05:36 UTCVendor advisory
  44. 2026-09-30 05:36 UTCGHSA enrichment
  45. 2026-09-30 01:25 UTCVendor advisory
  46. 2026-09-30 01:25 UTCGHSA enrichment
  47. 2026-09-29 21:15 UTCVendor advisory
  48. 2026-09-29 21:15 UTCGHSA enrichment
  49. 2026-09-29 17:02 UTCEG score recompute
  50. 2026-09-29 17:02 UTCVendor advisory
  51. 2026-09-29 17:01 UTCGHSA enrichment
  52. 2026-09-29 15:14 UTCEPSS rescore
  53. 2026-09-29 12:51 UTCVendor advisory
  54. 2026-09-29 12:51 UTCGHSA enrichment
  55. 2026-09-29 08:41 UTCVendor advisory
  56. 2026-09-29 08:41 UTCGHSA enrichment
  57. 2026-09-29 04:31 UTCVendor advisory
  58. 2026-09-29 04:31 UTCGHSA enrichment
  59. 2026-09-29 00:20 UTCEG score recompute
  60. 2026-09-29 00:20 UTCVendor advisory
  61. 2026-09-29 00:20 UTCGHSA enrichment
  62. 2026-09-28 20:10 UTCVendor advisory
  63. 2026-09-28 20:10 UTCGHSA enrichment
  64. 2026-09-28 16:00 UTCVendor advisory
  65. 2026-09-28 16:00 UTCGHSA enrichment
  66. 2026-09-28 11:50 UTCVendor advisory
  67. 2026-09-28 11:50 UTCGHSA enrichment
  68. 2026-09-28 07:40 UTCVendor advisory
  69. 2026-09-28 07:40 UTCGHSA enrichment
  70. 2026-09-28 03:30 UTCVendor advisory
  71. 2026-09-28 03:30 UTCGHSA enrichment
  72. 2026-09-27 23:20 UTCVendor advisory
  73. 2026-09-27 23:20 UTCGHSA enrichment
  74. 2026-09-27 21:51 UTCCISA KEV update
  75. 2026-09-27 19:10 UTCVendor advisory

Related CVEs(same product + same vendor + same CWE)

Frequently asked(6)

What is CVE-2020-35730?
CVE-2020-35730 is a critical vulnerability published on December 28, 2020. An XSS issue was discovered in Roundcube Webmail before 1.2.13, 1.3.x before 1.3.16, and 1.4.x before 1.4.10. The attacker can send a plain text e-mail message, with JavaScript in a link reference element that is mishandled by linkrefaddindex in rcubestring_replacer.php.
When was CVE-2020-35730 disclosed?
CVE-2020-35730 was first published on December 28, 2020, 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-2020-35730 actively exploited?
Yes. CISA added CVE-2020-35730 to the Known Exploited Vulnerabilities catalog on June 22, 2023, affecting Roundcube Roundcube Webmail. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. A fix is available. Apply it.
What is the CVSS score of CVE-2020-35730?
CVE-2020-35730 has a CVSS v3 base score of 6.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
Which products are affected by CVE-2020-35730?
CVE-2020-35730 affects Roundcube Roundcube Webmail. The affected packages EchelonGraph has on record, with version ranges, are listed in the Affected Packages section of this page.
How do I remediate CVE-2020-35730?
A fix for CVE-2020-35730 is available: update to the fixed version the vendor names in its advisory.

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