Weblate: Unverified REST API email changes

published 2026-08-26 2 mo ago modified 2026-09-09 1 mo ago also EUVD-2026-66710

cvss: 3.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 17%
public exploits: 0; none known

Weblate is a web based localization tool. Prior to 2026.8, an authenticated user can change the account's primary email through PUT or PATCH requests to /api/users/{username}/ without verifying the new address, allowing a later team invitation for that address to be accepted without access to the intended recipient's mailbox. This issue is fixed in version 2026.8.

Patch / fix

links 1

github.com/WeblateOrg/weblate#20639 pull request

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 mo ago (2026-08-27)

Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	3.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N

Affected products

WeblateOrg weblate

Classification

Weakness

CWE-302 Authentication Bypass by Assumed-Immutable Data
CWE-841 Improper Enforcement of Behavioral Workflow

References

Sources

CVE List CVE-2026-77508
NVD CVE-2026-77508

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary