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.
An official patch is available. Apply the patch as soon as possible.
CVSS v4.0 Metrics
Exploitability
Attack VectorLocal
ComplexityLow
RequirementsPresent
PrivilegesNone
User InteractionActive
Threat
Exploit MaturityPoC
Vulnerable System
ConfidentialityNone
IntegrityNone
AvailabilityHigh
Subsequent System
ConfidentialityNone
IntegrityNone
AvailabilityNone
Supplemental
SafetyNegligible
AutomatableYes
RecoveryAutomatic
Value DensityConcentrated
UrgencyMedium
Patch StatusOfficial Patch
Change Log
| Date | Source | Changes | Score |
|---|
| 2026-07-21 | PoC | E: U→P | 1.7 → 4.4 |
| 2026-07-21 | nvd | AV: P→L, AC: H→L, PR: H→N, VA: N→H | 0.0 → 1.7 |
| 2026-07-21 | nvd | patch: Unavailable→Official Patch | 0.0 → 0.0 |
| 2026-07-21 | cve.org | initial, patch: Unavailable | 0.0 |
Affected Software
| Vendor | Product | Version |
|---|
| cpp-peglib_project | cpp-peglib | ≤ 0.1.12 |
Published: 2021-04-21