CVE-2020-11958

re2c 1.3 has a heap-based buffer overflow in Scanner::fill in parse/scanner.cc via a long lexeme.

Published: 2020-04-21 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-11958 is rated Moderate Risk (53.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.46%). Review affected assets and schedule 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-2020-11958

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 2026-05-26 0.58% 0.46% -0.12%
2 2026-03-05 0.46% 0.58% +0.12%
3 2025-12-28 — 0.46% —

Full EPSS history (22 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-11958

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2020-11958

OS Trackers for CVE-2020-11958

vendor priority summary link
alpine high CVE-2020-11958: 1 source package rows (re2c); 9 state rows across 9 repos (3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 9, open 0. https://security.alpinelinux.org/vuln/CVE-2020-11958
debian not yet assigned CVE-2020-11958 not yet assigned priority: Debian including 1 source packages (re2c), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-11958
gentoo normal CVE-2020-11958: 1 GLSA(s) (202007-28), 1 atom(s) (dev-util/re2c); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-11958
redhat medium — https://access.redhat.com/security/cve/CVE-2020-11958
ubuntu medium CVE-2020-11958 medium priority: Ubuntu including 1 source packages (re2c), 6 status rows across 6 suites (bionic, eoan, focal, trusty, upstream, xenial): not-affected 3, released 2, needs-triage 1. https://ubuntu.com/security/CVE-2020-11958

Affected software / configurations for CVE-2020-11958

Vendor Product Version Raw CPE
re2c re2c 1.3 cpe:2.3:a:re2c:re2c:1.3:*:*:*:*:*:*:*
canonical ubuntu_linux 19.10 cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*
canonical ubuntu_linux 20.04 cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*

References for CVE-2020-11958

cvelogic Threat Intelligence