CVE-2026-35542
Roundcube: Bypass of remote image blocking via crafted BODY background attribute
CVE-2026-35542 is a medium vulnerability (CVSS 5.3) in Bulwarkmail Webmail, published April 3, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.42%, the 36th percentile. Fixed in roundcube/roundcubemail 1.7-rc5.
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
CVE-2026-35542- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-669
- Updated
- 2026-11-02
EUVDEUVD-2026-18587
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
EUVD-2026-18587- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-5hf6-crg4-fg59
Roundcube: Bypass of remote image blocking via crafted BODY background attribute
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
GHSA-5hf6-crg4-fg59- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-669
- Updated
- 2026-11-02
NVD
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
CVE-2026-35542- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-669
- Updated
- 2026-11-02
OSV
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
CVE-2026-35542- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-669
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-35542
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
DEBIAN-CVE-2026-35542- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVGHSA-5hf6-crg4-fg59
Roundcube: Bypass of remote image blocking via crafted BODY background attribute
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
GHSA-5hf6-crg4-fg59- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-669
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-35542
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
- Record
UBUNTU-CVE-2026-35542- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
roundcube/roundcubemailPackagist |
1.7-beta up to 1.7-rc5 | 1.7-rc5 |
roundcubeDebian:12 |
before 1.6.5+dfsg-1+deb12u8, plus listed versions 1.6.1+dfsg-11.6.2+dfsg-11.6.3+dfsg-11.6.3+dfsg-1~deb12u11.6.3+dfsg-2 Show 10 moreShow less1.6.4+dfsg-11.6.4+dfsg-1~deb12u11.6.5+dfsg-11.6.5+dfsg-1+deb12u21.6.5+dfsg-1+deb12u31.6.5+dfsg-1+deb12u41.6.5+dfsg-1+deb12u51.6.5+dfsg-1+deb12u61.6.5+dfsg-1+deb12u71.6.5+dfsg-1~deb12u1 |
1.6.5+dfsg-1+deb12u8 |
roundcubeDebian:13 |
before 1.6.15+dfsg-0+deb13u1, plus listed versions 1.6.11+dfsg-11.6.12+dfsg-0+deb13u11.6.12+dfsg-11.6.13+dfsg-0+deb13u11.6.13+dfsg-11.6.14+dfsg-1 |
1.6.15+dfsg-0+deb13u1 |
roundcubeDebian:14 |
before 1.6.14+dfsg-1, plus listed versions 1.6.11+dfsg-11.6.12+dfsg-11.6.13+dfsg-1 |
1.6.14+dfsg-1 |
roundcube/roundcubemailPackagist |
1.7-beta up to 1.7-rc5, plus listed versions 1.7-beta21.7-rc1.7-rc21.7-rc31.7-rc4 |
1.7-rc5 |
roundcubeUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 1.1.1+dfsg.1-21.1.2+dfsg.1-51.1.3+dfsg.1-11.1.4+dfsg.1-11.2~beta+dfsg.1-0ubuntu1 Show 8 moreShow less1.2~beta+dfsg.1-0ubuntu1+esm11.2~beta+dfsg.1-0ubuntu1+esm21.2~beta+dfsg.1-0ubuntu1+esm31.2~beta+dfsg.1-0ubuntu1+esm41.2~beta+dfsg.1-0ubuntu1+esm51.2~beta+dfsg.1-0ubuntu1+esm61.2~beta+dfsg.1-0ubuntu1+esm71.2~beta+dfsg.1-0ubuntu1+esm8 |
None known |
roundcubeUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 1.3.0+dfsg.1-11.3.1+dfsg.1-11.3.3+dfsg.1-11.3.3+dfsg.1-21.3.6+dfsg.1-1 Show 8 moreShow less1.3.6+dfsg.1-1ubuntu0.1~esm11.3.6+dfsg.1-1ubuntu0.1~esm21.3.6+dfsg.1-1ubuntu0.1~esm31.3.6+dfsg.1-1ubuntu0.1~esm41.3.6+dfsg.1-1ubuntu0.1~esm51.3.6+dfsg.1-1ubuntu0.1~esm61.3.6+dfsg.1-1ubuntu0.1~esm71.3.6+dfsg.1-1ubuntu0.1~esm8 |
None known |
roundcubeUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1.3.8+dfsg.1-21.3.10+dfsg.1-11.4.1+dfsg.1-21.4.2+dfsg.1-11.4.2+dfsg.1-2 Show 9 moreShow less1.4.3+dfsg.1-11.4.3+dfsg.1-1ubuntu0.1~esm11.4.3+dfsg.1-1ubuntu0.1~esm21.4.3+dfsg.1-1ubuntu0.1~esm31.4.3+dfsg.1-1ubuntu0.1~esm41.4.3+dfsg.1-1ubuntu0.1~esm51.4.3+dfsg.1-1ubuntu0.1~esm61.4.3+dfsg.1-1ubuntu0.1~esm71.4.3+dfsg.1-1ubuntu0.1~esm8 |
None known |
roundcubeUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 1.4.11+dfsg.1-41.5.0+dfsg.1-21.5.0+dfsg.1-2ubuntu0.1~esm11.5.0+dfsg.1-2ubuntu0.1~esm21.5.0+dfsg.1-2ubuntu0.1~esm31.5.0+dfsg.1-2ubuntu0.1~esm41.5.0+dfsg.1-2ubuntu0.1~esm51.5.0+dfsg.1-2ubuntu0.1~esm6 |
None known |
roundcubeUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 1.6.2+dfsg-11.6.4+dfsg-11.6.5+dfsg-11.6.6+dfsg-11.6.6+dfsg-2 Show 4 moreShow less1.6.6+dfsg-2ubuntu0.11.6.6+dfsg-2ubuntu0.1+esm11.6.6+dfsg-2ubuntu0.1+esm21.6.6+dfsg-2ubuntu0.1+esm3 |
None known |
roundcubeUbuntu:25.10 |
All versions, plus listed versions 1.6.10+dfsg-11.6.10+dfsg-21.6.11+dfsg-1 |
None known |
roundcubeUbuntu:26.10 |
All versions, plus listed versions 1.6.11+dfsg-1 |
None known |
roundcubeUbuntu:Pro:26.04:LTS |
All versions, plus listed versions 1.6.11+dfsg-11.6.11+dfsg-1ubuntu0.26.04.1~esm1 |
None known |
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-02 | created | CVE List, EUVD, GitHub Advisories, NVD, OSV |
References
roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14
github.com/roundcube/roundcubemail/releases/tag/1.7-rc5
Show 9 moreShow less
nvd.nist.gov/vuln/detail/CVE-2026-35542
security-tracker.debian.org/tracker/CVE-2026-35542
ubuntu.com/security/CVE-2026-35542
cve.org/CVERecord?id=CVE-2026-35542
nullcathedral.com/posts/2026-03-18-roundcube-round-two-three-more-sanitizer-bypasses