Weblate lacks rate limiting when verifying second factor

Description

Impact

The verification of the second factor was not subject to rate limiting. The absence of rate limiting on the second factor endpoint allows an attacker with valid credentials to automate OTP guessing.

Patches

This issue has been addressed in Weblate 5.12 via https://github.com/WeblateOrg/weblate/pull/14918.

References

Thanks to obscuredeer for reporting this issue at HackerOne.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-06-16 14:52:53 UTC
Updated
2025-06-17 17:16:11 UTC
GitHub reviewed
2025-06-16 14:52:53 UTC
NVD published
2025-06-16

EPSS Score

Score Percentile
0.20% 42.24%

CVSS Scores

Base score Version Severity Vector
4.9 3.1
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-307 Improper Restriction of Excessive Authentication Attempts

Credits

  • nijel (remediation_developer)
  • obscuredeer (reporter)
  • amCap1712 (remediation_reviewer)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
pip weblate < 5.12 5.12

References

cvelogic Threat Intelligence