An information disclosure vulnerability exists in the /proc/pid/syscall functionality of Linux Kernel 5.1 Stable and 5.4.66. More specifically, this issue has been introduced in v5.1-rc4 (commit 631b7abacd02b88f4b0795c08b54ad4fc3e7c7c0) and is still present in v5.10-rc4, so it’s likely that all versions in between are affected. An attacker can read /proc/pid/syscall to trigger this vulnerability, which leads to the kernel leaking memory contents.
CVSS v4.0 Metrics
Exploitability
Attack VectorLocal
ComplexityLow
RequirementsPresent
PrivilegesNone
User InteractionNone
Threat
Exploit MaturityPoC
Vulnerable System
ConfidentialityHigh
IntegrityNone
AvailabilityNone
Subsequent System
ConfidentialityNone
IntegrityNone
AvailabilityNone
Supplemental
SafetyNegligible
AutomatableYes
RecoveryAutomatic
Value DensityConcentrated
UrgencyMedium
Change Log
| Date | Source | Changes | Score |
|---|
| 2026-07-21 | PoC | E: U→P | 2.1 → 5.0 |
| 2026-07-21 | nvd | VC: L→H | 0.5 → 2.1 |
| 2026-07-21 | cve.org | initial, patch: Unavailable | 0.5 |
Affected Software
| Vendor | Product | Version |
|---|
| linux | linux_kernel | 5.10 |
| linux | linux_kernel | 5.4.66 |
| linux | linux_kernel | 5.9.8 |
| n/a | Linux Kernel | Linux Kernel v5.10-rc4,Linux Kernel v5.4.66,Linux Kernel v5.9.8 |
Published: 2021-05-10