CVE-2025-64508Bugsink vulnerable to unauthenticated remote DoS via crafted Brotli input
- 7.5HighCVSS base score
- 0.51%Exploitation in 30 daysEPSS · top 56% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Bugsink is a self-hosted error tracking tool. In versions prior to 2.0.5, brotli "bombs" (highly compressed brotli streams, such as many zeros) can be sent to the server. Since the server will attempt to decompress these streams before applying various maximums, this can lead to exhaustion of the available memory and thus a 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 version `2.0.5`. The vulnerability is similar to, but distinct from, another brotli-related problem in Bugsink, GHSA-rrx3-2x4g-mq2h/CVE-2025-64509.
Timeline
ID reserved
By GitHub_M
- 5 days later
· 5 days later
Published
- 2 days later
· 2 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Deferred | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.51% · top 56% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIbugsinkGHSA-fc2v-vcwj-269v (opens in a new tab)
References
References8
- https://github.com/bugsink/bugsink/security/advisories/GHSA-fc2v-vcwj-269v (opens in a new tab)x_refsource_CONFIRM
- https://github.com/google/brotli/issues/1327 (opens in a new tab)x_refsource_MISC
- https://github.com/google/brotli/issues/1375 (opens in a new tab)x_refsource_MISC
- https://github.com/bugsink/bugsink/pull/266 (opens in a new tab)x_refsource_MISC
- https://github.com/google/brotli/pull/1234 (opens in a new tab)x_refsource_MISC
- https://github.com/bugsink/bugsink/commit/3f65544aab3ad5303d97009136640de97b0676a5 (opens in a new tab)x_refsource_MISC
- https://github.com/google/brotli/commit/67d78bc41db1a0d03f2e763497748f2f69946627 (opens in a new tab)x_refsource_MISC
- https://github.com/google/brotli/releases/tag/v1.2.0 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-50818 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-fc2v-vcwj-269v (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-64508)Record last updated .