# CVE-2026-35537: roundcube: An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14

CVE-2026-35537 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-35537, released April 3, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-35537
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0048
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 3, 2026

## Description

An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Unsafe deserialization in the redis/memcache session handler may lead to arbitrary file write operations by unauthenticated attackers via crafted session data.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | roundcube Debian 12.15 (bookworm) | 1.6.5+dfsg-1+deb12u8 | [DEBIAN-CVE-2026-35537](https://patchblox.com/security/data/fix/linux/debian-cve-2026-35537.md) | Apr 3, 2026 |
| Linux | roundcube Debian 13.5 (trixie) | 1.6.15+dfsg-0+deb13u1 | [DEBIAN-CVE-2026-35537](https://patchblox.com/security/data/fix/linux/debian-cve-2026-35537.md) | Apr 3, 2026 |
| Linux | roundcube Debian 14 | 1.6.14+dfsg-1 | [DEBIAN-CVE-2026-35537](https://patchblox.com/security/data/fix/linux/debian-cve-2026-35537.md) | Apr 3, 2026 |
| Linux | roundcubemail opensuse-leap 16.0 | 1.6.15-bp160.1.1 | [OPENSUSE-SU-2026:20586-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20586-1.md) | Apr 17, 2026 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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