[krbdev.mit.edu #9085] git commit

[Greg Hudson via RT]

Mon Feb 13 21:57:14 2023: Request 9085 was acted upon.
 Transaction: Ticket created by ghudson at mit.edu
       Queue: krb5
     Subject: git commit
       Owner: ghudson at mit.edu
  Requestors: 
      Status: new
 Ticket <URL: https://krbdev.mit.edu/rt/Ticket/Display.html?id=9085 >



Fix read overruns in SPNEGO parsing

Fix three read overruns discovered by the GitHub Security Lab team
(GHSL-2023-016, GHSL-2023-017, and GHSL-2023-018) using OSS-Fuzz.

In get_mech_set(), error out if gss_add_oid_set_member() fails rather
than continue the loop and increment i past the current bound of
returned_mechSet.  In g_verify_neg_token_init(), check for zero-byte
sequences before reading tag bytes, and reduce cur_size by one to
account for the tag byte when calling gssint_get_der_length().

https://github.com/krb5/krb5/commit/47c2a12830dbd7fb8e13c239ddc0ac74129a91f6
Author: Greg Hudson <ghudson at mit.edu>
Commit: 47c2a12830dbd7fb8e13c239ddc0ac74129a91f6
Branch: master
 src/lib/gssapi/spnego/spnego_mech.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)