CVE-2021-47593
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2021-47593
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47593.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2021-47593
- Related
- Published
- 2024-06-19T15:15:53Z
- Modified
- 2024-11-01T16:48:21.432582Z
- Severity
-
- 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
- Summary
- [none]
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
mptcp: clear 'kern' flag from fallback sockets
The mptcp ULP extension relies on sk->sksockkern being set correctly: It prevents setsockopt(fd, IPPROTOTCP, TCPULP, "mptcp", 6); from working for plain tcp sockets (any userspace-exposed socket).
But in case of fallback, accept() can return a plain tcp sk. In such case, sk is still tagged as 'kernel' and setsockopt will work.
This will crash the kernel, The subflow extension has a NULL ctx->conn mptcp socket:
BUG: KASAN: null-ptr-deref in subflowdataready+0x181/0x2b0 Call Trace: tcpdataready+0xf8/0x370 [..]
- References
Affected packages
Debian:11 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source
Debian:12 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source
Debian:13 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source