The Hidden Service (HS) client implementation in Tor before 0.2.4.27, 0.2.5.x before 0.2.5.12, and 0.2.6.x before 0.2.6.7 allows remote servers to cause a denial of service (assertion failure and application exit) via a malformed HS descriptor.
Conclusion & alert: CVE-2015-2929 is rated Moderate Risk (52.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.16%). Mandatory action: Review affected assets and schedule 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 | 0.47% | 1.16% | +0.69% |
| 2 | 2025-03-30 | 0.97% | 0.47% | -0.51% |
| 3 | 2025-03-29 | — | 0.97% | — |
Full EPSS history (6 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2015-2929 not yet assigned priority: Debian including 1 source packages (tor), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2015-2929 |
gentoo
|
normal | CVE-2015-2929: 1 GLSA(s) (201507-02), 1 atom(s) (net-misc/tor); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2015-2929 |
ubuntu
|
medium | CVE-2015-2929 medium priority: Ubuntu including 1 source packages (tor), 10 status rows across 10 suites (lucid, precise, trusty, upstream, utopic, vivid, wily, xenial, yakkety, zesty): not-affected 4, released 3, ignored 2, DNE 1. | https://ubuntu.com/security/CVE-2015-2929 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| torproject | tor | < 0.2.4.27 | cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:* |
| torproject | tor | >= 0.2.5.1, < 0.2.5.12 | cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:* |
| torproject | tor | >= 0.2.6.1, < 0.2.6.7 | cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| http://openwall.com/lists/oss-security/2015/04/06/5 | Mailing List Third Party Advisory |
| https://trac.torproject.org/projects/tor/ticket/15601 | Vendor Advisory |