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🛡️ CVE-2026-35537 — webmail

🟢 CVSS 3.7 — Low ✅ No Known Exploit CWE-502 NVD
3.7
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Roundcube Webmail: Unsafe deserialization in the redis/memcache session handler

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.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is high, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity low, availability none.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: High — the attacker first has to win a race, learn a secret or otherwise prepare the target.
  • Privileges required: None — an unauthenticated stranger can try it.
  • User interaction: None — nobody has to be tricked into anything.
  • Scope: Unchanged — the damage stays inside the vulnerable component.
  • Confidentiality impact: None.
  • Integrity impact: Low — limited, and the attacker does not choose what is affected.
  • Availability impact: None.

Weakness class

CVE-2026-35537 is classified as CWE-502: Deserialization of Untrusted Data. Serialised data from an untrusted source is reconstructed into objects, which can trigger code during the process.

Affected software

CVE-2026-35537 is recorded against 2 packages.

  • roundcube/roundcubemail (from 1.7-beta up to 1.7-rc5)
  • webmail (from 1.6.0 up to 1.6.14)

Timeline and source

Published on 3 April 2026 and last revised on 14 April 2026. No public exploit is currently recorded for this entry. A vendor advisory or fix has been published. Record sourced from NVD.

References

nvd.nist.gov (Advisory)
github.com (Web)
github.com (Web)
github.com (Web)
github.com (Package)
github.com (Web)
github.com (Web)
github.com (Web)
roundcube.net (Web)
www.openwall.com (Web)

Other advisories for this package

roundcube/roundcubemail has other advisories on record. If you are patching this one, these are worth checking on the same host:

Same weakness in other software

These advisories are the same class of weakness (CWE-502: Deserialization of Untrusted Data) in other software:

CVE-2026-35537 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity LOW
CVSS Score 3.7
CVSS Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE CWE-502
Public Exploit ✅ No
Source NVD
Published 2026-04-03
Updated 2026-08-20
Modified 2026-04-14

Affected Packages

Software From version Fixed in
roundcube/roundcubemail 1.7-beta 1.7-rc5
webmail 1.6.0 1.6.14

Similar Threats

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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