diff options
| author | Noah Misch <noah@leadboat.com> | 2020-11-09 07:32:09 -0800 |
|---|---|---|
| committer | Noah Misch <noah@leadboat.com> | 2020-11-09 07:32:13 -0800 |
| commit | 3855e5b4767b189d4daf6e9a774e4e64be72e0ff (patch) | |
| tree | 62ac627c93c2f4c42795f0078213b8de3e080bf5 /src/bin/psql/common.c | |
| parent | ac8f6243cb002f3386322fb231a0c5daa637941d (diff) | |
Ignore attempts to \gset into specially treated variables.
If an interactive psql session used \gset when querying a compromised
server, the attacker could execute arbitrary code as the operating
system account running psql. Using a prefix not found among specially
treated variables, e.g. every lowercase string, precluded the attack.
Fix by issuing a warning and setting no variable for the column in
question. Users wanting the old behavior can use a prefix and then a
meta-command like "\set HISTSIZE :prefix_HISTSIZE". Back-patch to 9.5
(all supported versions).
Reviewed by Robert Haas. Reported by Nick Cleaton.
Security: CVE-2020-25696
Diffstat (limited to 'src/bin/psql/common.c')
| -rw-r--r-- | src/bin/psql/common.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c index 4b2679360fc..8cb924a861e 100644 --- a/src/bin/psql/common.c +++ b/src/bin/psql/common.c @@ -921,6 +921,13 @@ StoreQueryTuple(const PGresult *result) /* concatenate prefix and column name */ varname = psprintf("%s%s", pset.gset_prefix, colname); + if (VariableHasHook(pset.vars, varname)) + { + pg_log_warning("attempt to \\gset into specially treated variable \"%s\" ignored", + varname); + continue; + } + if (!PQgetisnull(result, 0, i)) value = PQgetvalue(result, 0, i); else |