CVE-2019-20838: apple macos Out-of-bounds Read
Vulnerability summary
CVE-2019-20838 is a high (CVSS 7.5) Out-of-bounds Read vulnerability in apple macos. EPSS estimates a 2.84% chance of exploitation in the next 30 days, higher than 86.6% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 3% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 7 · Related 5Timeline
- 15-06-2020PublishedVulnerability first disclosed.
- 08-10-2026Last modifiedVulnerability information updated.
Description
libpcre in PCRE before 8.43 allows a subject buffer over-read in JIT when UTF is disabled, and \X or \R has more than one fixed quantifier, a related issue to CVE-2019-20454.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
2.84%
Chance of exploitation in the next 30 days
Percentile
87%
Versus all other CVEs
30-day change
Increase +0.07 pp
From 2.77% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Apple1 product
- macos< 11.0.1
Debian1 product
- pcre3All versions (No fix recorded)
Pcre1 product
- pcre< 8.43
Splunk1 product
- universal_forwarder≥ 8.2.0, < 8.2.12 | ≥ 9.0.0, < 9.0.6 | 9.1.0
Ubuntu1 product
- pcre3< 2:8.39-9ubuntu0.1 | < 2:8.39-12ubuntu0.1 | < 2:8.39-13ubuntu0.22.04.1 | All versions (No fix recorded)
5 vendors · 5 products
