GHSA-xc85-32mf-xpv8 · Severity: medium · Ecosystem: rubygems — Rack arbitrary code execution via timing attack
Rack::Session::Cookie in Rack 1.5.x before 1.5.2, 1.4.x before 1.4.5, 1.3.x before 1.3.10, 1.2.x before 1.2.8, and 1.1.x before 1.1.6 allows remote attackers to guess the session cookie, gain privileges, and execute arbitrary code via a timing attack involving an HMAC comparison function that does not run in constant time.
Conclusion & alert: CVE-2013-0263 is rated Moderate Risk (47.4/100): CVSS Medium severity, with high exploitation likelihood (EPSS 5.28%, 91th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 16.07% | 5.28% | -10.79% |
| 2 | 2026-04-20 | 8.63% | 16.07% | +7.44% |
| 3 | 2026-03-26 | — | 8.63% | — |
Full EPSS history (13 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.1 | 2.0 | MEDIUM |
|
4.9 | 6.4 | [email protected] |
GHSA-xc85-32mf-xpv8 · Severity: medium · Ecosystem: rubygems — Rack arbitrary code execution via timing attack
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2013-0263 not yet assigned priority: Debian including 1 source packages (ruby-rack), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2013-0263 |
gentoo
|
high | CVE-2013-0263: 1 GLSA(s) (201405-10), 1 atom(s) (dev-ruby/rack); latest impact high. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2013-0263 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2013-0263 |
suse
|
medium | CVE-2013-0263 severity moderate: SUSE including 49 source package names (ruby2.1-rubygem-chef-10.32.2-3.1, ruby2.1-rubygem-chef-10.32.2-3.2, …), 51 product×package rows across 6 product lines (SUSE Cloud Compute Node for SUSE Linux Enterprise 12 5, SUSE Linux Enterprise Software Development Kit 11 SP4, … (6 product lines)): Fixed 47, Known Not Affected 4. | https://www.suse.com/security/cve/CVE-2013-0263/ |
ubuntu
|
medium | CVE-2013-0263 medium priority: Ubuntu including 1 source packages (ruby-rack), 15 status rows across 15 suites (hardy, lucid, oneiric, precise, quantal, raring, saucy, trusty, upstream, utopic, vivid, wily, xenial, yakkety, zesty): released 9, DNE 3, ignored 3. | https://ubuntu.com/security/CVE-2013-0263 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| rack_project | rack | 1.5.0 | cpe:2.3:a:rack_project:rack:1.5.0:*:*:*:*:*:*:* |
| rack_project | rack | 1.5.1 | cpe:2.3:a:rack_project:rack:1.5.1:*:*:*:*:*:*:* |
| rack_project | rack | 1.4.0 | cpe:2.3:a:rack_project:rack:1.4.0:*:*:*:*:*:*:* |
| rack_project | rack | 1.4.1 | cpe:2.3:a:rack_project:rack:1.4.1:*:*:*:*:*:*:* |
| rack_project | rack | 1.4.2 | cpe:2.3:a:rack_project:rack:1.4.2:*:*:*:*:*:*:* |
| rack_project | rack | 1.4.3 | cpe:2.3:a:rack_project:rack:1.4.3:*:*:*:*:*:*:* |
| rack_project | rack | 1.4.4 | cpe:2.3:a:rack_project:rack:1.4.4:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.0 | cpe:2.3:a:rack_project:rack:1.3.0:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.1 | cpe:2.3:a:rack_project:rack:1.3.1:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.2 | cpe:2.3:a:rack_project:rack:1.3.2:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.3 | cpe:2.3:a:rack_project:rack:1.3.3:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.4 | cpe:2.3:a:rack_project:rack:1.3.4:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.5 | cpe:2.3:a:rack_project:rack:1.3.5:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.6 | cpe:2.3:a:rack_project:rack:1.3.6:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.7 | cpe:2.3:a:rack_project:rack:1.3.7:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.8 | cpe:2.3:a:rack_project:rack:1.3.8:*:*:*:*:*:*:* |
| rack_project | rack | 1.3.9 | cpe:2.3:a:rack_project:rack:1.3.9:*:*:*:*:*:*:* |
| rack_project | rack | 1.2.0 | cpe:2.3:a:rack_project:rack:1.2.0:*:*:*:*:*:*:* |
| rack_project | rack | 1.2.1 | cpe:2.3:a:rack_project:rack:1.2.1:*:*:*:*:*:*:* |
| rack_project | rack | 1.2.2 | cpe:2.3:a:rack_project:rack:1.2.2:*:*:*:*:*:*:* |
| rack_project | rack | 1.2.3 | cpe:2.3:a:rack_project:rack:1.2.3:*:*:*:*:*:*:* |
| rack_project | rack | 1.2.4 | cpe:2.3:a:rack_project:rack:1.2.4:*:*:*:*:*:*:* |
| rack_project | rack | 1.2.6 | cpe:2.3:a:rack_project:rack:1.2.6:*:*:*:*:*:*:* |
| rack_project | rack | 1.2.7 | cpe:2.3:a:rack_project:rack:1.2.7:*:*:*:*:*:*:* |
| rack_project | rack | 1.1.0 | cpe:2.3:a:rack_project:rack:1.1.0:*:*:*:*:*:*:* |
| rack_project | rack | 1.1.4 | cpe:2.3:a:rack_project:rack:1.1.4:*:*:*:*:*:*:* |
| rack_project | rack | 1.1.5 | cpe:2.3:a:rack_project:rack:1.1.5:*:*:*:*:*:*:* |
| rack_project | rack | 1.1.6 | cpe:2.3:a:rack_project:rack:1.1.6:*:*:*:*:*:*:* |