Apache Karaf: LDAP filter injection in JAAS LDAP login modules
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 4.4.12
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: yes
- Technical impact: partial
Summary
LDAPCache and LDAPBackingEngine build LDAP search filters for user lookup and role lookup by textually substituting the placeholders %u, %dn, and %fqdn (drawn from the login name, the resolved user DN, and its fully qualified namespace form) into administrator-configured filter templates (userFilter, roleFilter). Before the fix, the only sanitization applied to the substituted value was double backslashed: filter = filter.replaceAll(Pattern.quote("%u"), Matcher.quoteReplacement(user)); filter = filter.replace("\\", "\\\\"); This does not escape the other characters RFC 4515 requires escaping in an LDAP search filter: *, (, ), and NUL. A login name containing any of these can change the structure of the resulting filter rather than being matched as a literal value (e.g. a crafted username can turn an equality match into a wildcard match, or close/reopen filter clauses), widening what the search returns and potentially causing a login or role lookup to match an LDAP entry other than the intended one, over-granting roles, and depending on deployment-specific filter templates, potentially affecting which account a login resolved to. It's not exploitable through every entry points: LDAPLoginModule and LDAPPubkeyLoginModule both called Util.doRFC2254Encoding() (correct RFC 4515 escaping) on the login name before handing it to LDAPCache, which masked the missing escaping in LDAPCache for those two call paths. Using LDAPCache directly (bypassing the login modules) does not reproduce through the normal LDAPLoginModule/LDAPPubkeyLoginModule authentication flow for this reason. It does reproduce through two other call paths that reach LDAPCache/LDAPBackingEngine without any prior escaping: • GSSAPILdapLoginModule passes the NameCallback name straight through, unescaped. • LDAPBackingEngine (listRoles) passes principal.getName() straight through, unescaped.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- org.apache.karaf.jaas.modules.ldap
fixed in 4.4.12