CVE-2026-114731

Medium 5.3

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by an uncontrolled resource consumption vulnerability in the CSS proxy (the utils/modcss action). The fetched stylesheet was read into memory in full, with no size limit and no read timeout, so a stylesheet URL referencing an attacker-controlled host could be used to exhaust server memory. Upstream fixed this in the commit “Add a size limit to the CSS proxy content processing”, which caps the response at 5 MB, reads it as a stream and applies a read timeout.

Assigner
mitre
Published
2026-10-22
Updated
2026-10-22
Reserved
2026-10-22

Scores

SourceCVSSScoreSeverityVector
mitre3.15.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weaknesses

Affected

VendorProductVersions
Roundcube Webmail 1.6.0 to < 1.6.20 (affected)
1.7.0 to < 1.7.5 (affected)
others: unaffected

References

Full CVE JSON record (5.2)

API · GitHub · cve.org

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