CVE-2026-26201
published 2026-02-19CVE-2026-26201: emp3r0r is a C2 designed by Linux users for Linux environments. Prior to version 3.21.2, multiple shared maps are accessed without consistent synchronization…
PriorityP341high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.29%
20.7th percentile
emp3r0r is a C2 designed by Linux users for Linux environments. Prior to version 3.21.2, multiple shared maps are accessed without consistent synchronization across goroutines. Under concurrent activity, Go runtime can trigger `fatal error: concurrent map read and map write`, causing C2 process crash (availability loss). Version 3.21.2 fixes this issue.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github.com | jm33-m0_emp3r0r_core | >= 0 < 0.0.0-20260212232424-ea4d074f081d | 0.0.0-20260212232424-ea4d074f081d |
| jm33-m0 | emp3r0r | < 3.21.2 | 3.21.2 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.07.0HIGHCVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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OSV
emp3r0r Affected by Concurrent Map Access DoS (panic/crash) in github.com/jm33-m0/emp3r0r/core
osv·2026-02-23
CVE-2026-26201 emp3r0r Affected by Concurrent Map Access DoS (panic/crash) in github.com/jm33-m0/emp3r0r/core
emp3r0r Affected by Concurrent Map Access DoS (panic/crash) in github.com/jm33-m0/emp3r0r/core
emp3r0r Affected by Concurrent Map Access DoS (panic/crash) in github.com/jm33-m0/emp3r0r/core
OSV
emp3r0r Affected by Concurrent Map Access DoS (panic/crash)
osv·2026-02-17
CVE-2026-26201 [HIGH] emp3r0r Affected by Concurrent Map Access DoS (panic/crash)
emp3r0r Affected by Concurrent Map Access DoS (panic/crash)
## Summary
Multiple shared maps are accessed without consistent synchronization across goroutines. Under concurrent activity, Go runtime can trigger `fatal error: concurrent map read and map write`, causing C2 process crash (availability loss).
## Vulnerable Component(with code examples)
Operator relay map had mixed access patterns (iteration and mutation without a single lock policy):
```go
// vulnerable pattern (operator session map)
for sessionID, op := range OPERATORS { // iteration path
...
}
// concurrent mutation path elsewhere
OPERATORS[operatorSession] = &operator_t{...}
delete(OPERATORS, operatorSession)
```
Port-forwarding session map had read/write paths guarded inconsistently:
```go
// vulnerable pattern (port
GHSA
emp3r0r Affected by Concurrent Map Access DoS (panic/crash)
ghsa·2026-02-17
CVE-2026-26201 [HIGH] CWE-362 emp3r0r Affected by Concurrent Map Access DoS (panic/crash)
emp3r0r Affected by Concurrent Map Access DoS (panic/crash)
## Summary
Multiple shared maps are accessed without consistent synchronization across goroutines. Under concurrent activity, Go runtime can trigger `fatal error: concurrent map read and map write`, causing C2 process crash (availability loss).
## Vulnerable Component(with code examples)
Operator relay map had mixed access patterns (iteration and mutation without a single lock policy):
```go
// vulnerable pattern (operator session map)
for sessionID, op := range OPERATORS { // iteration path
...
}
// concurrent mutation path elsewhere
OPERATORS[operatorSession] = &operator_t{...}
delete(OPERATORS, operatorSession)
```
Port-forwarding session map had read/write paths guarded inconsistently:
```go
// vulnerable pattern (port
No detection rules found.
No public exploits indexed.
2026-02-19
Published