CVE-2019-11808
Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Ratpack
Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.
- Record
CVE-2019-11808- CVSS 3.0
- 3.7 Low
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:P/I:N/A:N - Weakness
- CWE-338
- Updated
- 2026-11-02
CVE List No score
Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.
- Record
CVE-2019-11808- Updated
- 2026-11-02
EUVDEUVD-2019-0451 No score
Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.
- Record
EUVD-2019-0451- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-54mg-vgrp-mwx9
Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Ratpack
Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.
- Record
GHSA-54mg-vgrp-mwx9- CVSS 3.0
- 3.7 Low
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-338
- Updated
- 2026-11-02
OSV
Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.
- Record
CVE-2019-11808- CVSS 3.0
- 3.7 Low
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVGHSA-54mg-vgrp-mwx9
Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Ratpack
Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.
- Record
GHSA-54mg-vgrp-mwx9- CVSS 3.0
- 3.7 Low
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-338
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
io.ratpack:ratpack-sessionMaven |
before 1.6.1 | 1.6.1 |
io.ratpack:ratpack-javaMaven |
before 1.6.1 | 1.6.1 |
io.ratpack:ratpack-groovyMaven |
before 1.6.1 | 1.6.1 |
io.ratpack:ratpack-sessionMaven |
before 1.6.1, plus listed versions 0.9.00.9.10.9.100.9.110.9.12 Show 45 moreShow less0.9.130.9.140.9.150.9.160.9.170.9.180.9.190.9.20.9.30.9.40.9.50.9.60.9.70.9.80.9.91.0.01.0.0-rc-11.0.0-rc-21.0.0-rc-31.1.01.1.11.2.01.2.0-RC-11.2.0-rc-21.3.01.3.0-rc-11.3.0-rc-21.3.11.3.21.3.31.4.01.4.0-rc-11.4.0-rc-21.4.0-rc-31.4.11.4.21.4.31.4.41.4.51.4.61.5.01.5.11.5.21.5.31.5.4 |
1.6.1 |
io.ratpack:ratpack-groovyMaven |
before 1.6.1, plus listed versions 0.9.00.9.10.9.100.9.110.9.12 Show 45 moreShow less0.9.130.9.140.9.150.9.160.9.170.9.180.9.190.9.20.9.30.9.40.9.50.9.60.9.70.9.80.9.91.0.01.0.0-rc-11.0.0-rc-21.0.0-rc-31.1.01.1.11.2.01.2.0-RC-11.2.0-rc-21.3.01.3.0-rc-11.3.0-rc-21.3.11.3.21.3.31.4.01.4.0-rc-11.4.0-rc-21.4.0-rc-31.4.11.4.21.4.31.4.41.4.51.4.61.5.01.5.11.5.21.5.31.5.4 |
1.6.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-11808 is a low vulnerability (CVSS 3.7) in Ratpack Project Ratpack, published May 7, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.31%, the 70th percentile. Fixed in io.ratpack:ratpack-session 1.6.1.
References
Left out here: 10 versions. The JSON record has them.