CVE-2026-50127
Weblate SSRF: outbound URL guard misses the NAT64 well-known prefix (64:ff9b::/96)
Weblate is a web based localization tool. From version 5.15 to before version 2026.6, Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions. This issue has been patched in version 2026.6.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Weblate SSRF: outbound URL guard misses the NAT64 well-known prefix (64:ff9b::/96)
Weblate is a web based localization tool. From version 5.15 to before version 2026.6, Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions. This issue has been patched in version 2026.6.
- Record
CVE-2026-50127- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
EUVDEUVD-2026-36113
Weblate is a web based localization tool. From version 5.15 to before version 2026.6, Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions. This issue has been patched in version 2026.6.
- Record
EUVD-2026-36113- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-vmfc-9982-2m45
Weblate SSRF: outbound URL guard misses some private ranges
Impact
Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions.
Patches
Resources
The issue was reported by @tonghuaroot via GitHub, and the same user also provided the initial patch.
- Record
GHSA-vmfc-9982-2m45- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
NVD
Weblate is a web based localization tool. From version 5.15 to before version 2026.6, Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions. This issue has been patched in version 2026.6.
- Record
CVE-2026-50127- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
OSV
Weblate SSRF: outbound URL guard misses the NAT64 well-known prefix (64:ff9b::/96)
Weblate is a web based localization tool. From version 5.15 to before version 2026.6, Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions. This issue has been patched in version 2026.6.
- Record
CVE-2026-50127- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
OSVGHSA-vmfc-9982-2m45
Weblate SSRF: outbound URL guard misses some private ranges
Impact
Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions.
Patches
Resources
The issue was reported by @tonghuaroot via GitHub, and the same user also provided the initial patch.
- Record
GHSA-vmfc-9982-2m45- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
OSVPYSEC-2026-3416
Weblate SSRF: outbound URL guard misses some private ranges
Impact
Weblate's VCS_RESTRICT_PRIVATE did not properly account for some transitional IPv6 ranges, multicast addresses, or some semi-private IPv4 ranges, which allowed some addresses to bypass private range restrictions.
Patches
Resources
The issue was reported by @tonghuaroot via GitHub, and the same user also provided the initial patch.
- Record
PYSEC-2026-3416- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVopenSUSE-SU-2026:11051-1 No score
weblate-5.17.1-2.1 on GA media
These are all security issues fixed in the weblate-5.17.1-2.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:11051-1- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-50127 is a medium vulnerability (CVSS 5.9) in Weblateorg Weblate, published June 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.31%, the 23rd percentile. Fixed in weblate 2026.6.
References
github.com/WeblateOrg/weblate/security/advisories/GHSA-vmfc-9982-2m45
nvd.nist.gov/vuln/detail/CVE-2026-50127