bind9/lib
Ondřej Surý 9bdace3fa3
Fix GSS-API context leak in TKEY negotiation
Reject multi-round GSS-API negotiation (GSS_S_CONTINUE_NEEDED) in
dst_gssapi_acceptctx().  Each call to gss_accept_sec_context()
allocates a context inside the GSS library; without this fix, the
context handle was passed back to process_gsstkey() which did not
store it persistently, leaking it on every incomplete negotiation.

An unauthenticated attacker could exhaust server memory by sending
repeated TKEY queries with GSSAPI tokens, each leaking one GSS
context.  The leaked memory is allocated by the GSS library via
malloc(), bypassing BIND's memory accounting.

In practice, Kerberos/SPNEGO (the only mechanism used with BIND)
completes in a single round, so rejecting continuation does not
affect real-world deployments.  See RFC 3645 Section 4.1.3.

(cherry picked from commit 3d8e0d068f08694282c5ecd3bd6c332de6c75485)
2026-05-07 13:09:18 +02:00
..
dns Fix GSS-API context leak in TKEY negotiation 2026-05-07 13:09:18 +02:00
isc Remove OpenSSL memory tracking support from the tls.c module 2026-05-06 13:57:52 +00:00
isccc Remove redundant parentheses from the return statement 2024-11-19 14:26:52 +01:00
isccfg Fix KASP key leaks on keystore lookup failure 2026-03-16 11:05:03 +01:00
ns Apply XFR-out quota after ACL is checked 2026-05-07 13:09:18 +02:00
.gitignore The isc/platform.h header has been completely removed 2021-07-06 05:33:48 +00:00
Makefile.am Move irs_resconf into libdns and remove libirs 2023-02-24 09:38:59 +00:00