CVE-2021-29480
MEDIUMDescription
Ratpack is a toolkit for creating web applications. In versions prior to 1.9.0, the client side session module uses the application startup time as the signing key by default. This means that if an attacker can determine this time, and if encryption is not also used (which is recommended, but is not on by default), the session data could be tampered with by someone with the ability to write cookies. The default configuration is unsuitable for production use as an application restart renders all sessions invalid and is not multi-host compatible, but its use is not actively prevented. As of Ratpack 1.9.0, the default value is a securely randomly generated value, generated at application startup time. As a workaround, supply an alternative signing key, as per the documentation's recommendation.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Exploit Intelligence
Low risk: more likely to be exploited than 18% of all known CVEs.
References
Related Vulnerabilities
Other CWE-340 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2026-11374 | Critical | 9.0 | 2.0% | - | - |
| CVE-2024-47945 | Critical | 9.8 | 0.9% | - | Fix |
| CVE-2024-28957 | Medium | 5.3 | 0.8% | - | - |
| CVE-2020-1905 | Low | 3.3 | 0.6% | - | Fix |
| CVE-2025-40931 | Critical | 9.1 | 0.6% | - | - |
| CVE-2026-3256 | Critical | 9.8 | 0.5% | - | - |
Common questions
How do I fix CVE-2021-29480?
Upgrade ratpack to 1.9.0 or later.
Is CVE-2021-29480 being actively exploited?
Not that we know of. CVE-2021-29480 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.26% is the estimated probability that it will be exploited in the next 30 days. That is higher than 18% of all scored CVEs.
How severe is CVE-2021-29480?
CVE-2021-29480 has a CVSS v3 base score of 4.4, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2021-29480 affect?
Published advisories record a fix for ratpack (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2021-29480
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.