CVE-2026-75538 PUBLISHED

A Signed Length Overflow in Erlang/OTP's inet TCP Driver Overflows the Receive Buffer Into BEAM VM Memory From an Unauthenticated Peer

Assigner: EEF
Reserved: 20.08.2026 Published: 01.09.2026 Updated: 01.09.2026

An attacker that connects to an open Erlang TCP port that uses the inet driver with {packet,4} mode can use a signed overflow in an incorrect packet length calculation to overflow the receive buffer into the VM allocator area and beyond up to about 2 GB.

This would easily trash the allocated block's allocator metadata footer, and the next block, if any, and most likely cause the BEAM VM to crash. Utilizing this with precision enough to achieve Remote Code Execution would be extremely unfeasible.

This issue affects OTP from OTP 17.0 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to erts from 6.0 before 15.2.7.13, from 16.0 before 16.4.0.6, and from 17.0 before 17.0.6. Whether OTP before OTP 17.0, corresponding to erts before 6.0, is affected is unknown.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.2

Product Status

Vendor Erlang
Product OTP
Versions Default: unaffected
  • unknown from 0 to 17.0 (excl.)
  • affected from 17.0 to 27.3.4.17 (excl.)
  • affected from 28.0 to 28.5.0.6 (excl.)
  • affected from 29.0 to 29.0.6 (excl.)
Vendor Erlang
Product OTP
Versions Default: unaffected
  • unknown from 0 to 6.0 (excl.)
  • affected from 6.0 to 15.2.7.13 (excl.)
  • affected from 16.0 to 16.4.0.6 (excl.)
  • affected from 17.0 to 17.0.6 (excl.)
Vendor Erlang
Product OTP
Versions Default: unaffected
  • affected from 84adefa331c4159d432d22840663c38f155cd4c1 to 08e8efdba8500d2d6f54c6b1de1492b228017c9b (excl.)

Credits

  • Arthur Chan finder
  • David Korczynski finder
  • Adam Korcz finder
  • RaimoNiskanen / Ericsson remediation developer
  • Sverker Eriksson / Ericsson remediation reviewer
  • John Högberg / Ericsson remediation reviewer

References

Problem Types

  • CWE-190 Integer Overflow or Wraparound CWE
  • CWE-122 Heap-based Buffer Overflow CWE

Impacts

  • CAPEC-100 Overflow Buffers