OMERO webclient does not validate URL redirects on login or switching group.
Background
OMERO.web supports redirection to a given URL after performing login or switching the group context. These URLs are not validated, allowing redirection to untrusted sites. OMERO.web 5.9.0 adds URL validation before redirecting. External URLs are not considered valid, unless specified in the omero.web.redirect_allowed_hosts setting.
Impact
OMERO.web before 5.9.0
Patches
5.9.0
Workarounds
No workaround
References
For more information
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Affected software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | omero-web | < 5.9.0 | 5.9.0 |
References
- https://github.com/ome/omero-web/blob/master/CHANGELOG.md#590-march-2021
- https://pypi.org/project/omero-web/
- https://github.com/ome/omero-web/commit/952f8e5d28532fbb14fb665982211329d137908c
- https://www.openmicroscopy.org/security/advisories/2021-SV2/
- https://github.com/ome/omero-web/security/advisories/GHSA-g4rf-pc26-6hmr
- https://nvd.nist.gov/vuln/detail/CVE-2021-21377
- https://github.com/ome/omero-web
- https://github.com/pypa/advisory-database/tree/main/vulns/omero-web/PYSEC-2021-32.yaml
- https://pypi.org/project/omero-web
- https://www.openmicroscopy.org/security/advisories/2021-SV2
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N- Weakness (CWE)
CWE-601- Platform
- Python (PyPI)
- Package
omero-web- Disclosed
- 23.03.2021
- Updated
- 11.10.2026 13:19
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2021-32 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-g4rf-pc26-6hmr - CC BY 4.0
Vulnerability history: omero-web
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 7
- First → latest
- 06.2020 11.2025
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 1
- Medium 4
- Low 1
Disclosures per year
- 2020: 1
- 2021: 3
- 2022: 0
- 2023: 0
- 2024: 1
- 2025: 2
- 2026: 0
-
OMERO webclient does not validate URL redirects on login or switching group. this entry
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