Exploitation evidence
Known exploited · CISA KEV listed
Added 2023-06-22. Ransomware campaign use: Unknown.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2023-07-13. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
n/a / n/a
Default status: Not specified
- affected: n/a
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
CVE Program record ↗ · Download tracked evidence as JSON
- https://roundcube.net/download/
- https://github.com/roundcube/roundcubemail/compare/1.4.9...1.4.10
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=978491
- https://www.alexbirnberg.com/roundcube-xss.html
- https://github.com/roundcube/roundcubemail/releases/tag/1.4.10
- https://github.com/roundcube/roundcubemail/releases/tag/1.3.16
- https://github.com/roundcube/roundcubemail/releases/tag/1.2.13
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HMLIZWKMTRCLU7KZLEQHELS4INXJ7X5Q/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HCEU4BM5WGIDJWP6Z4PCH62ZMH57QYM2/
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-35730
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.3292,
"percentile": 0.98379
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.3292,
"percentile": 0.98369
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.3292,
"percentile": 0.98367
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.3292,
"percentile": 0.98367
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.3292,
"percentile": 0.98366
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.3292,
"percentile": 0.98364
}06 Nov 2026, 06:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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"url": "https://github.com/roundcube/roundcubemail/compare/1.4.9...1.4.10"
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"url": "https://www.alexbirnberg.com/roundcube-xss.html"
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],
"title": "CVE Program Container"
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"scope": "CHANGED",
"userInteraction": "REQUIRED",
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"version": "3.1"
}
},
{
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"timestamp": "2025-02-04T20:21:48.700288Z",
"version": "2.0.3"
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"url": "https://www.alexbirnberg.com/roundcube-xss.html"
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"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.4.10"
},
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],
"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.3.16"
},
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"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.2.13"
},
{
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"tags": [
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"x_refsource_FEDORA"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HMLIZWKMTRCLU7KZLEQHELS4INXJ7X5Q/"
},
{
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"refsource": "MISC",
"url": "https://roundcube.net/download/"
},
{
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"refsource": "CONFIRM",
"url": "https://github.com/roundcube/roundcubemail/compare/1.4.9...1.4.10"
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{
"name": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=978491",
"refsource": "CONFIRM",
"url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=978491"
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{
"name": "https://www.alexbirnberg.com/roundcube-xss.html",
"refsource": "MISC",
"url": "https://www.alexbirnberg.com/roundcube-xss.html"
},
{
"name": "https://github.com/roundcube/roundcubemail/releases/tag/1.4.10",
"refsource": "CONFIRM",
"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.4.10"
},
{
"name": "https://github.com/roundcube/roundcubemail/releases/tag/1.3.16",
"refsource": "CONFIRM",
"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.3.16"
},
{
"name": "https://github.com/roundcube/roundcubemail/releases/tag/1.2.13",
"refsource": "CONFIRM",
"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.2.13"
},
{
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"refsource": "FEDORA",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/HMLIZWKMTRCLU7KZLEQHELS4INXJ7X5Q/"
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},
"cveMetadata": {
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"assignerShortName": "mitre",
"cveId": "CVE-2020-35730",
"datePublished": "2020-12-28T19:37:08.000Z",
"dateReserved": "2020-12-27T00:00:00.000Z",
"dateUpdated": "2025-10-21T23:35:31.104Z",
"state": "PUBLISHED"
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}05 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.3292,
"percentile": 0.98363
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.3292,
"percentile": 0.98362
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.3292,
"percentile": 0.98359
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.3292,
"percentile": 0.98357
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2020-35730",
"cwes": [
"CWE-79"
],
"dateAdded": "2023-06-22",
"dueDate": "2023-07-13",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://roundcube.net/news/2020/12/27/security-updates-1.4.10-1.3.16-and-1.2.13; https://nvd.nist.gov/vuln/detail/CVE-2020-35730",
"product": "Roundcube Webmail",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "Roundcube Webmail contains a cross-site scripting (XSS) vulnerability that allows an attacker to send a plain text e-mail message with Javascript in a link reference element that is mishandled by linkref_addinindex in rcube_string_replacer.php.",
"vendorProject": "Roundcube",
"vulnerabilityName": "Roundcube Webmail Cross-Site Scripting (XSS) Vulnerability"
}