USN-8624-1: Sinatra vulnerability
It was discovered that Sinatra did not properly handle header parsing, causing ETag generation to hang when given specific input. A remote attacker could possibly use this issue to cause a denial of service.
CSIRTS triage
- What
- A vulnerability in header parsing can cause ETag generation to hang, leading to a denial of service.
- Who is affected
- All deployments of Sinatra are potentially affected by this issue.
- Urgency
- Remediation is necessary to prevent potential denial of service attacks.
- Action
- Update to the latest version of Sinatra to resolve this vulnerability.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch Sinatra
Get an email when a new Sinatra advisory drops — max one per day, one-click unsubscribe.
Details
Original advisory: https://ubuntu.com/security/notices/USN-8624-1
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2025-619210.46% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2025-61921 | coverage & exploitation status | NVD · CVE.org |
More from Ubuntu Security Notices
- highUSN-8620-4: Linux kernel (Intel IoTG) vulnerabilities2026-07-31
- highUSN-8620-3: Linux kernel (Intel IoTG) vulnerabilities2026-07-31
- unknownUSN-8625-1: OpenSSL vulnerability2026-07-30
- unknownUSN-8623-1: Linux kernel (NVIDIA) vulnerabilities2026-07-29
- unknownUSN-8622-1: Linux kernel (NVIDIA) vulnerabilities2026-07-29