Description
Ruby (aka CRuby) before 1.8.7-p357 computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 6.0 | ruby1.8 | 1.8.7.302-2squeeze3 | DLA-88-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | ruby +8 | 1.8.7.352-4.el6_2 | RHSA-2012:0069 |
| RHEL 5 | ruby +8 | 1.8.5-22.el5_7.1 | RHSA-2012:0070 |
| RHEL 4 | irb +6 | 1.8.1-18.el4 | RHSA-2012:0070 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | ruby3.3 +5 | 3.3.10-23.1.hum1 | RHSA-2026:7305 |
| Red Hat Hardened Images 1 | ruby3.4 +5 | 3.4.8-31.1.hum1 | RHSA-2026:7307 |
| Red Hat Hardened Images 1 | ruby4.0 +5 | 4.0.0-33.3.hum1 | RHSA-2026:8838 |
Advisories 6
- RHSA-2026:7305 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 6, 2026
- RHSA-2026:8838 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 6, 2026
- RHSA-2026:7307 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 6, 2026
- RHSA-2012:0070 Red Hat Security Advisory: ruby security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2012:0069 Red Hat Security Advisory: ruby security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DLA-88-1 ruby1.8 - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- 47405 third-party-advisory
- 1026474 vdb-entry
- http://www.nruns.com/_downloads/advisory28122011.pdf
- 47822 third-party-advisory
- RHSA-2012:0070 vendor-advisory
- JVN#90615481 third-party-advisory
- ruby-hash-dos(72020) vdb-entry
- VU#903934 third-party-advisory
- [ruby-talk] 20111228 [ANN] ruby 1.8.7 patchlevel 357 released mailing-list
- http://www.ruby-lang.org/en/news/2011/12/28/denial-of-service-attack-was-found-for-rubys-hash-algorithm/
- 20111228 n.runs-SA-2011.004 - web programming languages and platforms - DoS through hash table mailing-list
- RHSA-2012:0069 vendor-advisory
- http://support.apple.com/kb/HT5281
- APPLE-SA-2012-05-09-1 vendor-advisory
- JVNDB-2012-000066 third-party-advisory
- http://www.ocert.org/advisories/ocert-2011-003.html