CVE-2024-8158 json
User impersonation for lib9p based 9p fileservers
published 2024-08-25 2 y ago modified 2026-06-17 4 mo ago also EUVD-2024-48983
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 31%
- public exploits
- 0
- none known
Summary
A bug in the 9p authentication implementation within lib9p allows an attacker with an existing valid user within the configured auth server to impersonate any other valid filesystem user.
This is due to lib9p not properly verifying that the uname given in the Tauth and Tattach 9p messages matches the client UID returned from the factotum authentication handshake.
The only filesystem making use of these functions within the base 9front systems is the experimental hjfs disk filesystem, other disk filesystems (cwfs and gefs) are not affected by this bug.
This bug was inherited from Plan 9 and is present in all versions of 9front and is remedied fully in commit 9645ae07eb66a59015e3e118d0024790c37400da.
Patch / fix
- 9front 9front 9645ae07eb66a59015e3e118d0024790c37400da
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
0.38% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.8 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/AU:N/V:C/RE:L/U:Red |
| CNA | 4.0 | 8.8 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/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:N/R:X/V:C/RE:L/U:Red |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
Affected products
- 9front 9front
Classification
- Weakness
-
- CWE-639 Authorization Bypass Through User-Controlled Key
References
Sources
- CVE List CVE-2024-8158
- NVD CVE-2024-8158
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