libceph: define and enforce CEPH_MAX_KEY_LEN

Summary

In the Linux kernel, the following vulnerability has been resolved: libceph: define and enforce CEPH_MAX_KEY_LEN When decoding the key, verify that the key material would fit into a fixed-size buffer in process_auth_done() and generally has a sane length. The new CEPH_MAX_KEY_LEN check replaces the existing check for a key with no key material which is a) not universal since CEPH_CRYPTO_NONE has to be excluded and b) doesn't provide much value since a smaller than needed key is just as invalid as no key -- this has to be handled elsewhere anyway.

Timeline

1. May 8, 2026, 1:11 PM UTCCVE published
2. Oct 16, 2026, 3:16 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: total

3. Oct 19, 2026, 7:16 PM UTCRecord last updated

Affected versions

• Linux Linux

  From cd1a677cad994021b19665ed476aea63f5d54f31 · fixed in 6405e8c680974bb74e2c98d5249fb52c7b12a6c6; From cd1a677cad994021b19665ed476aea63f5d54f31 · fixed in 8d745d38c88ecbed95f6b2b39857bf89f35a3244; From cd1a677cad994021b19665ed476aea63f5d54f31 · fixed in e1dc45d97975f9db65694d234fbddf1915176e16; From cd1a677cad994021b19665ed476aea63f5d54f31 · fixed in 1b275bd49e58752efb83767a5d1aed41356c5e64; From cd1a677cad994021b19665ed476aea63f5d54f31 · fixed in c1a0f5f1e5e7e98c36a362ec3d1fcfd9932931ed; From cd1a677cad994021b19665ed476aea63f5d54f31 · fixed in d82467c07b03a27c3c5469b62bb3b726305a80bb; From cd1a677cad994021b19665ed476aea63f5d54f31 · fixed in ac431d597a9bdfc2ba6b314813f29a6ef2b4a3bf

• Linux Linux

  5.11

• KernelLinux

  From 5.11.0 · fixed in 5.15.202; From 5.16.0 · fixed in 6.1.165; From 6.2.0 · fixed in 6.6.128; From 6.7.0 · fixed in 6.12.75; From 6.13.0 · fixed in 6.18.16; From 6.19.0 · fixed in 6.19.6

References 7