CVE-2021-43411
When trying to exec a setuid executable, there's a window of time when the process already has the new privileges, but still refers to the old task and is accessible through the old process port.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
An issue was discovered in GNU Hurd before 0.9 20210404-9. When trying to exec a setuid executable, there's a window of time when the process already has the new privileges, but still refers to the old task and is accessible through the old process port. This can be exploited to get full root access.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.27% probability · 68th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-362
- Affected
- gnu/hurd
- Source
- cve@mitre.org
References
- https://lists.gnu.org/archive/html/bug-hurd/2021-05/msg00079.htmlExploit, Mailing List, Vendor Advisory
- https://salsa.debian.org/hurd-team/hurd/-/blob/4d1b079411e2f40576e7b58f9b5b78f733a2beda/debian/patches/0034-proc-Use-UIDs-for-evaluating-permissions.patchMailing List, Patch, Third Party Advisory
- https://www.mail-archive.com/bug-hurd%40gnu.org/msg32112.html
- https://lists.gnu.org/archive/html/bug-hurd/2021-05/msg00079.htmlExploit, Mailing List, Vendor Advisory
- https://salsa.debian.org/hurd-team/hurd/-/blob/4d1b079411e2f40576e7b58f9b5b78f733a2beda/debian/patches/0034-proc-Use-UIDs-for-evaluating-permissions.patchMailing List, Patch, Third Party Advisory
- https://www.mail-archive.com/bug-hurd%40gnu.org/msg32112.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.