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.

Published: 2026-06-10 Last update: 2026-06-10 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-50127 is rated Low Risk (31.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.29%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-50127

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.03% 0.29% +0.26%
2 2026-06-11 0.03%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-50127

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.2 3.6 [email protected]

Weakness enumeration for CVE-2026-50127

Affected software / configurations for CVE-2026-50127

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-50127

cvelogic Threat Intelligence