DCMTK through 3.6.6 does not handle string copy properly. Sending specific requests to the dcmqrdb program, it would query its database and copy the result even if the result is null, which can incur a head-based overflow. An attacker can use it to launch a DoS attack.
Conclusion & alert: CVE-2021-41689 is rated Moderate Risk (55/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.35%). Core evidence: EPSS rose +1.25% over the last day, indicating growing attacker interest. 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 | 0.10% | 1.35% | +1.25% |
| 2 | 2025-11-21 | 0.60% | 0.10% | -0.50% |
| 3 | 2025-11-18 | — | 0.60% | — |
Full EPSS history (10 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] |
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2021-41689 not yet assigned priority: Debian including 1 source packages (dcmtk), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2021-41689 |
ubuntu
|
medium | CVE-2021-41689 medium priority: Ubuntu including 1 source packages (dcmtk), 14 status rows across 14 suites (bionic, focal, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 7, released 5, DNE 1, ignored 1. | https://ubuntu.com/security/CVE-2021-41689 |
| URL | Tags |
|---|---|
| https://github.com/DCMTK/dcmtk | Product Third Party Advisory |
| https://github.com/DCMTK/dcmtk/commit/5c14bf53fb42ceca12bbcc0016e8704b1580920d | Patch Third Party Advisory |
| https://lists.debian.org/debian-lts-announce/2024/06/msg00022.html | |
| https://lists.debian.org/debian-lts-announce/2025/01/msg00032.html |