4.3

CVE-2026-25916: roundcube webmail Unprotected Alternate Channel

CVSS: 4.3v3.1MediumDeferred
AliasesUBUNTU-CVE-2026-25916DEBIAN-CVE-2026-25916
Published 09-02-2026Last modified 09-02-2026
Open JSON

Vulnerability summary

CVE-2026-25916 is a medium (CVSS 4.3) Unprotected Alternate Channel vulnerability in roundcube webmail. EPSS estimates a 0.54% chance of exploitation in the next 30 days, higher than 44.4% of scored vulnerabilities.

Overall risk
17/100
0100
Low · default modelHow is this calculated?
CVSS score
4.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.54%
0%100%
Low · -0.11 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 4 · Related 2
DLA-4480-1DSA-6137-1MGASA-2026-0065OPENSUSE-SU-2026:20323-1USN-8223-1

Timeline

  1. 09-02-2026
    PublishedVulnerability first disclosed.
  2. 09-02-2026
    Last modifiedVulnerability information updated.

Description

Roundcube Webmail before 1.5.13 and 1.6 before 1.6.13, when "Block remote images" is used, does not block SVG feImage.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.54%

Chance of exploitation in the next 30 days

Percentile

44%

Versus all other CVEs

30-day change

-0.11 pp

From 0.65% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.54%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • roundcube< 1.6.5+dfsg-1+deb12u7 | < 1.6.13+dfsg-0+deb13u1 | < 1.6.13+dfsg-1
Roundcube1 product
  • webmail< 1.5.13 | ≥ 1.6.0, < 1.6.13
Ubuntu1 product
  • roundcube< 1.3.6+dfsg.1-1ubuntu0.1~esm8 | < 1.4.3+dfsg.1-1ubuntu0.1~esm8 | < 1.5.0+dfsg.1-2ubuntu0.1~esm6 | < 1.6.6+dfsg-2ubuntu0.1+esm3 | All versions (No fix recorded)

3 vendors · 3 products

References

8 links