i think upgrade is a preferable solution lest we field repeated emails/jiras about vulnerability scanners detecting it.
On Fri, Dec 10, 2021 at 6:24 AM Uwe Schindler <u...@thetaphi.de> wrote: > With log4j 2.15.0 this should be fixed and by default all expansions on > log messages were disabled: > https://issues.apache.org/jira/browse/LOG4J2-3198 > > ----- > Uwe Schindler > Achterdiek 19, D-28357 Bremen > https://www.thetaphi.de > eMail: u...@thetaphi.de > > > -----Original Message----- > > From: Uwe Schindler <u...@thetaphi.de> > > Sent: Friday, December 10, 2021 11:10 AM > > To: dev@solr.apache.org > > Subject: RE: Log4J RCE vulnerability > > > > In general the sysprop "log4j2.formatMsgNoLookups=true" fix is the only > > correct fix (maybe add it to the bootstrap class of solr). Updating > log4j is not > > really needed. This prevents any of those shit. There's no reason ever > to parse > > ${} escapes in log messages. The only place where this can be used is the > > format pattern in the config file, but WTF was the idea behind that to > pass ALL > > log messages through the expansion? > > > > Man man, SNEAKY log4j!!! 😊 > > > > Uwe > > > > ----- > > Uwe Schindler > > Achterdiek 19, D-28357 Bremen > > https://www.thetaphi.de > > eMail: u...@thetaphi.de > > > > > -----Original Message----- > > > From: Uwe Schindler <u...@thetaphi.de> > > > Sent: Friday, December 10, 2021 10:35 AM > > > To: dev@solr.apache.org > > > Subject: RE: Log4J RCE vulnerability > > > > > > Hi, > > > > > > I did some checks: > > > - The problem also exists with logging parameters, so it is also > executed if you > > > call (which is IMHO a design failure in log4j, the reason for this is > that the > > > expansion is happending on printing the complete formatted log string > to the > > > output file): logger.info("Foobar: {}", "${badPayload}") > > > - It also triggers if the message of an exception has a malicous > payload! So > > > happens easily if some input is validated and there's an > > > IllegalArgumentException logged on validation errors > > > > > > To try out, and see it live do the following (can be done on any > server, I tested > > > it on my own servers, worked always): > > > > > > Start a local netcat: > > > root@pangaea-mw1:~# nc -lp 1234 > > > > > > Go to any user interface of you application, e.g. solr or send a query > > containing > > > this payload, e.g. as part of a query string that is logged: > > > ${jndi:ldap://127.0.0.1:1234/abc} > > > > > > You will see cryptic text with emojis in the above netcat output. This > shows > > > that it definitely made an external request. > > > > > > We should fix this in 8.11 by doing the following: > > > a) add "-Dlog4j2.formatMsgNoLookups=true" to Solr's start scripts > (easy fix, I > > > did the same on all my servers). Add this to the *main shell script*, > not to the > > > solr.sh.in files, as those are modified by users. > > > b) possibly update log4j, but with above fix it's not urgent and > should not be > > > done in 10.0. > > > > > > Uwe > > > > > > ----- > > > Uwe Schindler > > > Achterdiek 19, D-28357 Bremen > > > https://www.thetaphi.de > > > eMail: u...@thetaphi.de > > > > > > > -----Original Message----- > > > > From: Bram Van Dam <bram.van...@intix.eu> > > > > Sent: Friday, December 10, 2021 8:31 AM > > > > To: dev@solr.apache.org > > > > Subject: Log4J RCE vulnerability > > > > > > > > Heads up: > > > > > > > > Seems like there's a pretty severe remote code execution > vulnerability > > > > [1] in Log4J. Basically any application that uses log4j and that > allows > > > > user input to be injected into a logging string is susceptible. This > > > > probably includes Solr. > > > > > > > > Further interesting discussion on Hacker News [2] > > > > > > > > [1] https://www.lunasec.io/docs/blog/log4j-zero-day/ > > > > [2] https://news.ycombinator.com/item?id=29504755 > > > > > > > > > > > > - Bram > > > > > > > > --------------------------------------------------------------------- > > > > To unsubscribe, e-mail: dev-unsubscr...@solr.apache.org > > > > For additional commands, e-mail: dev-h...@solr.apache.org > > > > > > > > > --------------------------------------------------------------------- > > > To unsubscribe, e-mail: dev-unsubscr...@solr.apache.org > > > For additional commands, e-mail: dev-h...@solr.apache.org > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: dev-unsubscr...@solr.apache.org > > For additional commands, e-mail: dev-h...@solr.apache.org > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@solr.apache.org > For additional commands, e-mail: dev-h...@solr.apache.org > > -- http://www.needhamsoftware.com (work) http://www.the111shift.com (play)
