An invalid memory address dereference was discovered in the canUnpack function in p_mach.cpp in UPX 3.95 via a crafted Mach-O file.
Conclusion & alert: CVE-2019-20053 is rated Exploit Available (57.1/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.35%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
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 | 2026-05-27 | 0.36% | 0.35% | -0.02% |
| 2 | 2025-11-21 | 0.20% | 0.36% | +0.16% |
| 3 | 2025-11-18 | — | 0.20% | — |
Full EPSS history (12 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | [email protected] |
| 4.3 | 2.0 | MEDIUM |
|
8.6 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
medium | CVE-2019-20053: 1 source package rows (upx); 7 state rows across 7 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 7, open 0. | https://security.alpinelinux.org/vuln/CVE-2019-20053 |
debian
|
unimportant | CVE-2019-20053 unimportant priority: Debian including 1 source packages (upx-ucl), 4 status rows across 4 suites (bullseye, forky, sid, trixie): resolved 4. | https://security-tracker.debian.org/tracker/CVE-2019-20053 |
ubuntu
|
medium | CVE-2019-20053 medium priority: Ubuntu including 1 source packages (upx-ucl), 18 status rows across 18 suites (bionic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 11, needs-triage 4, ignored 2, DNE 1. | https://ubuntu.com/security/CVE-2019-20053 |
| URL | Tags |
|---|---|
| http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00003.html | Mailing List Third Party Advisory |
| http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00007.html | Mailing List Third Party Advisory |
| https://github.com/upx/upx/issues/314 | Exploit Third Party Advisory |