CVE-2025-64509 json
Bugsink vulnerable to unauthenticated remote DoS via crafted Brotli input (via CPU)
published 11mo ago modified 4mo ago also GHSA-rrx3-2x4g-mq2h , PYSEC-2026-1227 , EUVD-2025-50819
- cvss
- 7.5
- 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 27%
- public exploits
- 0
- none known
Summary
Bugsink is a self-hosted error tracking tool. In versions prior to 2.0.6, a specially crafted Brotli-compressed envelope can cause Bugsink to spend excessive CPU time in decompression, leading to denial of service. This can be done if the DSN is known, which it is in many common setups (JavaScript, Mobile Apps). The issue is patched in Bugsink 2.0.6. The vulnerability is similar to, but distinct from, another brotli-related problem in Bugsink, GHSA-fc2v-vcwj-269v/CVE-2025-64508.
Patch / fix
Is CVE-2025-64509 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 11mo ago
Exploit prediction
0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| OSV | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | bugsink | <2.0.6 |
2.0.6 |
Affected products
- bugsink bugsink
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
github.com
/bugsink/bugsink/commit/1201f754e39265d2aac58edf49dc380bac334388
web
-
github.com
/bugsink/bugsink/security/advisories/GHSA-rrx3-2x4g-mq2h
web
-
nvd.nist.gov
/vuln/detail/CVE-2025-64509
advisory
-
github.com
/bugsink/bugsink
package
-
pypi.org
/project/bugsink
package
-
github.com
/advisories/GHSA-rrx3-2x4g-mq2h
advisory
Sources
- CVE List CVE-2025-64509
- GitHub Advisory GHSA-rrx3-2x4g-mq2h
- NVD CVE-2025-64509
- OSV PYSEC-2026-1227
Fencer Intel 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.