CVE-2021-47152

Summary

In the Linux kernel, the following vulnerability has been resolved:

mptcp: fix data stream corruption

Maxim reported several issues when forcing a TCP transparent proxy to use the MPTCP protocol for the inbound connections. He also provided a clean reproducer.

The problem boils down to 'mptcp_frag_can_collapse_to()' assuming that only MPTCP will use the given page_frag.

If others - e.g. the plain TCP protocol - allocate page fragments, we can end-up re-using already allocated memory for mptcp_data_frag.

Fix the issue ensuring that the to-be-expanded data fragment is located at the current page frag end.

v1 -> v2:

  • added missing fixes tag (Mat)

Affected Software

VendorProductVersion RangeStatus
LinuxLinux18b683bff89d46ace55f12d00c0440d44d6160c4 < 3267a061096efc91eda52c2a0c61ba76e46e4b34affected
LinuxLinux18b683bff89d46ace55f12d00c0440d44d6160c4 < 18e7f0580da15cac1e79d73683ada5a9e70980f8affected
LinuxLinux18b683bff89d46ace55f12d00c0440d44d6160c4 < 29249eac5225429b898f278230a6ca2baa1ae154affected
LinuxLinux5.7affected
LinuxLinux0 < 5.7unaffected
LinuxLinux5.10.42 <= 5.10.*unaffected
LinuxLinux5.12.9 <= 5.12.*unaffected
LinuxLinux5.13 <= *unaffected

Weaknesses

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References