CVE-2019-1549 | Fork Protection

OpenSSL 1.1.1 introduced a rewritten random number generator (RNG). This was intended to include protection in the event of a fork() system call in order to ensure that the parent and child processes did not share the same RNG state. However this protection was not being used in the default case. A partial mitigation for this issue is that the output from a high precision timer is mixed into the RNG state so the likelihood of a parent and child process sharing state is significantly reduced. If an application already calls OPENSSL_init_crypto() explicitly using OPENSSL_INIT_ATFORK then this problem does not occur at all. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c).

Published: 2019-09-10 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-1549 is rated Moderate Risk (57.2/100): CVSS Medium severity, with high exploitation likelihood (EPSS 6.23%, 93th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +3.60% over the last day, indicating growing attacker interest. 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.

Exploit prediction scoring system (EPSS) score for CVE-2019-1549

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 2.63% 6.23% +3.60%
2 2026-05-31 3.05% 2.63% -0.42%
3 2026-04-21 — 3.05% —

Full EPSS history (36 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-1549

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2019-1549

OS Trackers for CVE-2019-1549

vendor priority summary link
alpine medium CVE-2019-1549: 3 source package rows (openssl, openssl1.1-compat, openssl3); 25 state rows across 13 repos (3.10-main, 3.11-main, 3.12-main, 3.17-community, 3.17-main, 3.18-community, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-community, edge-main); fixed 15, open 10. https://security.alpinelinux.org/vuln/CVE-2019-1549
debian not yet assigned CVE-2019-1549 not yet assigned priority: Debian including 1 source packages (openssl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2019-1549
redhat low — https://access.redhat.com/security/cve/CVE-2019-1549
suse medium — https://www.suse.com/security/cve/CVE-2019-1549/
ubuntu low CVE-2019-1549 low priority: Ubuntu including 4 source packages (edk2, nodejs, openssl, openssl1.0), 36 status rows across 9 suites (bionic, disco, eoan, focal, groovy, hirsute, trusty, upstream, xenial): not-affected 17, DNE 8, released 6, needs-triage 3, ignored 2. https://ubuntu.com/security/CVE-2019-1549

Affected software / configurations for CVE-2019-1549

Vendor Product Version Raw CPE
openssl openssl >= 1.1.1, <= 1.1.1c cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*

References for CVE-2019-1549

URL Tags
https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=1b0fe00e2704b5e20334a16d3c9099d1ba2ef1be
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GY6SNRJP2S7Y42GIIDO3HXPNMDYN2U3A/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZN4VVQJ3JDCHGIHV4Y2YTXBYQZ6PWQ7E/
https://seclists.org/bugtraq/2019/Oct/1
https://security.netapp.com/advisory/ntap-20190919-0002/
https://support.f5.com/csp/article/K44070243
https://support.f5.com/csp/article/K44070243?utm_source=f5support&amp%3Butm_medium=RSS
https://usn.ubuntu.com/4376-1/
https://www.debian.org/security/2019/dsa-4539
https://www.openssl.org/news/secadv/20190910.txt Vendor Advisory
https://www.oracle.com/security-alerts/cpuapr2020.html
https://www.oracle.com/security-alerts/cpujan2020.html
https://www.oracle.com/security-alerts/cpujul2020.html
https://www.oracle.com/security-alerts/cpuoct2020.html
https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html
cvelogic Threat Intelligence