What is CVE-2020-23914?

CVE-2020-23914 is a medium-severity vulnerability in Cpp-Peglib Project, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2021-04-21.

How severe is CVE-2020-23914?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Is CVE-2020-23914 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

NULL pointer dereference in Cpp-Peglib Project

CVE-2020-23914

An issue was discovered in cpp-peglib through v0.1.12. A NULL pointer dereference exists in the peg::AstOptimizer::optimize() located in peglib.h. It allows an attacker to cause Denial of Service.

Published 2021-04-21 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.009 (57.2th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 57.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Cpp-Peglib Project

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

Public proof-of-concept exploits

References

github.com/yhirose/cpp-peglib/issues/121 (Exploit, Third Party Advisory)
github.com/yhirose/cpp-peglib/commit/0061f393de54cf0326621c079dc2988336d1ebb3 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2020-23914?: CVE-2020-23914 is a medium-severity vulnerability in Cpp-Peglib Project, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2021-04-21.
How severe is CVE-2020-23914?: Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2020-23914 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.