{"id":"CVE-2026-54899","aliases":["DEBIAN-CVE-2026-54899","EUVD-2026-40848","GHSA-2cw7-v8ff-p88r","UBUNTU-CVE-2026-54899"],"status":"published","title":"Oj: Use-After-Free in Oj::Parser Symbol Key Cache Toggle","description":"Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to version 3.17.2, disabling symbol_keys on a reused Oj::Parser instance triggers a heap use-after-free. When symbol_keys is toggled from true to false, opt_symbol_keys_set frees the internal key cache (cache_free) but does not clear the pointer. The next parse call reads from the freed cache via cache_intern, producing a use-after-free. This issue has been fixed in version 3.17.2.","severity":{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-08","score":0.00407,"percentile":0.35244,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-416"],"published":"2026-06-19T19:34:30Z","modified":"2026-10-26T11:47:26Z","fixes":[{"ecosystem":"RubyGems","package":"oj","fixed_in":["3.17.2"],"sources":["ghsa","osv"]},{"ecosystem":"Debian:12","package":"ruby-oj","fixed_in":["3.14.2-1+deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"ruby-oj","fixed_in":["3.16.3-1+deb13u1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"ruby-oj","fixed_in":["3.17.3-1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"RubyGems","package":"oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.17.2"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.14.2-1+deb12u1"}]}],"versions":["3.14.2-1"]},{"source":"osv","ecosystem":"Debian:13","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.16.3-1+deb13u1"}]}],"versions":["3.16.3-1"]},{"source":"osv","ecosystem":"Debian:14","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.17.3-1"}]}],"versions":["3.16.12-1","3.16.15-1","3.16.16-1","3.16.3-1","3.17.0-1","3.17.1-1"]},{"source":"osv","ecosystem":"RubyGems","package":"oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.17.2"}]}],"versions":["0.5","0.5.1","0.5.2","0.6.0","0.7.0","0.8.0","0.9.0","1.0.0","1.0.1","1.0.2","1.0.3","1.0.4","1.0.5","1.0.6","1.1.0","1.1.1","1.2.0","1.2.1","1.2.10","1.2.11","1.2.12","1.2.13","1.2.2","1.2.3","1.2.4","1.2.5","1.2.6","1.2.7","1.2.8","1.2.9","1.3.0","1.3.2","1.3.4","1.3.5","1.3.6","1.3.7","1.4.0","1.4.1","1.4.2","1.4.3","1.4.4","1.4.5","1.4.6","1.4.6a2","1.4.7","2.0.0","2.0.1","2.0.10","2.0.11","2.0.12","2.0.13","2.0.14","2.0.2","2.0.3","2.0.4","2.0.5","2.0.6","2.0.7","2.0.8","2.0.9","2.1.0","2.1.1","2.1.2","2.1.3","2.1.4","2.1.6","2.1.7","2.10.0","2.10.1","2.10.2","2.10.3","2.10.4","2.11.0","2.11.1","2.11.2","2.11.3","2.11.4","2.11.5","2.12.0","2.12.1","2.12.10","2.12.11","2.12.12","2.12.13","2.12.14","2.12.2","2.12.3","2.12.4","2.12.5","2.12.6","2.12.7","2.12.8","2.12.9","2.13.0","2.13.1","2.14.0","2.14.1","2.14.2","2.14.3","2.14.4","2.14.5","2.14.6","2.15.0","2.15.1","2.16.0","2.16.1","2.17.0","2.17.1","2.17.2","2.17.3","2.17.4","2.17.5","2.18.0","2.18.1","2.18.2","2.18.3","2.18.4","2.18.5","2.2.0","2.2.1","2.2.2","2.2.3","2.3.0","2.4.0","2.4.1","2.4.2","2.4.3","2.5.1","2.5.2","2.5.3","2.5.4","2.5.5","2.6.0","2.6.1","2.7.0","2.7.1","2.7.2","2.7.3","2.8.0","2.8.1","2.9.0","2.9.1","2.9.2","2.9.3","2.9.4","2.9.5","2.9.6","2.9.7","2.9.8","2.9.9","3.0.0","3.0.1","3.0.10","3.0.11","3.0.2","3.0.3","3.0.4","3.0.5","3.0.6","3.0.7","3.0.8","3.0.9","3.1.0","3.1.2","3.1.3","3.1.4","3.10.0","3.10.1","3.10.10","3.10.11","3.10.12","3.10.13","3.10.14","3.10.15","3.10.16","3.10.17","3.10.18","3.10.2","3.10.3","3.10.5","3.10.6","3.10.7","3.10.8","3.10.9","3.11.0","3.11.1","3.11.2","3.11.3","3.11.4","3.11.5","3.11.6","3.11.7","3.11.8","3.12.0","3.12.1","3.12.2","3.12.3","3.13.0","3.13.1","3.13.10","3.13.11","3.13.12","3.13.13","3.13.14","3.13.15","3.13.16","3.13.17","3.13.18","3.13.19","3.13.2","3.13.20","3.13.21","3.13.22","3.13.23","3.13.3","3.13.4","3.13.5","3.13.6","3.13.7","3.13.8","3.13.9","3.14.0","3.14.1","3.14.2","3.14.3","3.15.0","3.15.1","3.16.0","3.16.1","3.16.10","3.16.11","3.16.12","3.16.13","3.16.14","3.16.15","3.16.16","3.16.17","3.16.2","3.16.3","3.16.4","3.16.5","3.16.6","3.16.7","3.16.8","3.16.9","3.17.0","3.17.1","3.2.0","3.2.1","3.3.0","3.3.1","3.3.10","3.3.2","3.3.3","3.3.4","3.3.5","3.3.6","3.3.7","3.3.8","3.3.9","3.4.0","3.5.0","3.5.1","3.6.0","3.6.10","3.6.11","3.6.12","3.6.13","3.6.2","3.6.3","3.6.4","3.6.5","3.6.6","3.6.7","3.6.8","3.6.9","3.7.0","3.7.1","3.7.10","3.7.11","3.7.12","3.7.2","3.7.3","3.7.4","3.7.5","3.7.6","3.7.7","3.7.8","3.7.9","3.8.0","3.8.1","3.9.0","3.9.1","3.9.2"]},{"source":"osv","ecosystem":"Ubuntu:14.04:LTS","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.10-1","2.1.4-1","2.4.0-1","2.5.3-1"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.12.10-3","2.12.10-3build1","2.12.10-4","2.12.10-4build1"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.17.4-1","3.4.0-1","3.4.0-1build1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.8.1-1","3.9.1-1","3.9.2-1","3.10.1-1","3.10.1-1build1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.11.0-1","3.13.7-1","3.13.7-1build1","3.13.9-1","3.13.9-1build1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.15.0-1","3.16.1-1","3.16.3-1","3.16.3-1build1","3.16.3-1build2"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.16.3-1build3"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.16.15-1","3.17.0-1","3.17.1-1","3.17.3-1","3.17.4-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"ruby-oj","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.16.3-1build3","3.16.12-1","3.16.15-1"]}],"products":[{"vendor":"ohler55","product":"oj"}],"references":[{"url":"https://github.com/ohler55/oj/security/advisories/GHSA-2cw7-v8ff-p88r","tags":["x_refsource_CONFIRM","exploit","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54899","tags":["advisory"]},{"url":"https://github.com/rubysec/ruby-advisory-db/blob/master/gems/oj/CVE-2026-54899.yml","tags":["web"]},{"url":"https://www.cve.org/CVERecord/SearchResults?query=CVE-2026-54899","tags":["web"]},{"url":"https://github.com/advisories/GHSA-2cw7-v8ff-p88r"},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-54899","tags":["advisory"]},{"url":"https://github.com/ohler55/oj","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-54899","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-54899","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-54899","title":"Oj: Use-After-Free in Oj::Parser Symbol Key Cache Toggle","description":"Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to version 3.17.2, disabling symbol_keys on a reused Oj::Parser instance triggers a heap use-after-free. When symbol_keys is toggled from true to false, opt_symbol_keys_set frees the internal key cache (cache_free) but does not clear the pointer. The next parse call reads from the freed cache via cache_intern, producing a use-after-free. This issue has been fixed in version 3.17.2.","status":"published","published":"2026-06-30T23:03:15.696Z","modified":"2026-07-01T14:26:28.538Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T13:38:09.774038Z"}],"euvd":[{"id":"EUVD-2026-40848","description":"Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to version 3.17.2, disabling symbol_keys on a reused Oj::Parser instance triggers a heap use-after-free. When symbol_keys is toggled from true to false, opt_symbol_keys_set frees the internal key cache (cache_free) but does not clear the pointer. The next parse call reads from the freed cache via cache_intern, producing a use-after-free. This issue has been fixed in version 3.17.2.","status":"published","published":"2026-06-30T23:03:15Z","modified":"2026-07-01T14:26:28Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T18:20:19.829772Z"}],"ghsa":[{"id":"GHSA-2cw7-v8ff-p88r","title":"Oj: Use-After-Free in Oj::Parser Symbol Key Cache Toggle","description":"### Summary\n\nDisabling `symbol_keys` on a reused `Oj::Parser` instance triggers a heap use-after-free. When `symbol_keys` is toggled from `true` to `false`, `opt_symbol_keys_set` frees the internal key cache (`cache_free`) but does not clear the pointer. The next `parse` call reads from the freed cache via `cache_intern`, producing a use-after-free.\n\n### Version\n\n- **Software**: oj gem\n- **Affected**: all versions with `ext/oj/usual.c`\n- **Latest tested**: 3.17.1 (confirmed present)\n\n### Details\n\n`ext/oj/usual.c`, `opt_symbol_keys_set`:\n\n```c\n// usual.c:1043–1051\nif (symbol_keys) {\n    d-\u003ekey_cache = cache_create(...);   // allocate\n} else {\n    cache_free(d-\u003ekey_cache);           // free — but d-\u003ekey_cache pointer not NULLed\n}\n```\n\nOn the next parse call, `cache_key` → `cache_intern` reads from `d-\u003ekey_cache` which now points to freed memory.\n\nASAN report:\n```\n==145265==ERROR: AddressSanitizer: heap-use-after-free on address 0x50b00001a318\nREAD of size 8 at 0x50b00001a318 thread T0\n    #0 cache_intern            /ext/oj/cache.c:328\n    #1 cache_key               /ext/oj/usual.c:161\n    #2 close_object            /ext/oj/usual.c:285\n    #3 parse                   /ext/oj/parser.c:693\n    #4 parser_parse            /ext/oj/parser.c:1408\nfreed by thread T0 here:\n    #0 free\n    #1 cache_free              /ext/oj/cache.c:277\n    #2 opt_symbol_keys_set     /ext/oj/usual.c:1051\n    #3 option                  /ext/oj/usual.c:1111\n    #4 parser_missing          /ext/oj/parser.c:1362\n0x50b00001a318 is 40 bytes inside freed 112-byte region [fd]fd fd fd fd fd fd fd\n```\n\n### Reproduce\n\n```ruby\nrequire 'oj'\np = Oj::Parser.new(:usual, symbol_keys: true)\np.symbol_keys = false     # frees cache without nulling pointer\np.parse('{\"attacker\":1}') # UAF: reads freed cache\n```","status":"published","published":"2026-06-19T19:34:30Z","modified":"2026-10-06T19:52:38Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T14:41:28.013673Z"}],"nvd":[{"id":"CVE-2026-54899","description":"Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to version 3.17.2, disabling symbol_keys on a reused Oj::Parser instance triggers a heap use-after-free. When symbol_keys is toggled from true to false, opt_symbol_keys_set frees the internal key cache (cache_free) but does not clear the pointer. The next parse call reads from the freed cache via cache_intern, producing a use-after-free. This issue has been fixed in version 3.17.2.","status":"published","published":"2026-07-01T00:16:33.22Z","modified":"2026-10-25T17:10:00.197Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T14:12:27.199837Z"}],"osv":[{"id":"DEBIAN-CVE-2026-54899","description":"Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to version 3.17.2, disabling symbol_keys on a reused Oj::Parser instance triggers a heap use-after-free. When symbol_keys is toggled from true to false, opt_symbol_keys_set frees the internal key cache (cache_free) but does not clear the pointer. The next parse call reads from the freed cache via cache_intern, producing a use-after-free. This issue has been fixed in version 3.17.2.","status":"published","published":"2026-07-01T00:16:33.22Z","modified":"2026-10-26T11:47:26.092143024Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"updated_at":"2026-11-02T15:45:57.236551Z"},{"id":"GHSA-2cw7-v8ff-p88r","title":"Oj: Use-After-Free in Oj::Parser Symbol Key Cache Toggle","description":"### Summary\n\nDisabling `symbol_keys` on a reused `Oj::Parser` instance triggers a heap use-after-free. When `symbol_keys` is toggled from `true` to `false`, `opt_symbol_keys_set` frees the internal key cache (`cache_free`) but does not clear the pointer. The next `parse` call reads from the freed cache via `cache_intern`, producing a use-after-free.\n\n### Version\n\n- **Software**: oj gem\n- **Affected**: all versions with `ext/oj/usual.c`\n- **Latest tested**: 3.17.1 (confirmed present)\n\n### Details\n\n`ext/oj/usual.c`, `opt_symbol_keys_set`:\n\n```c\n// usual.c:1043–1051\nif (symbol_keys) {\n    d-\u003ekey_cache = cache_create(...);   // allocate\n} else {\n    cache_free(d-\u003ekey_cache);           // free — but d-\u003ekey_cache pointer not NULLed\n}\n```\n\nOn the next parse call, `cache_key` → `cache_intern` reads from `d-\u003ekey_cache` which now points to freed memory.\n\nASAN report:\n```\n==145265==ERROR: AddressSanitizer: heap-use-after-free on address 0x50b00001a318\nREAD of size 8 at 0x50b00001a318 thread T0\n    #0 cache_intern            /ext/oj/cache.c:328\n    #1 cache_key               /ext/oj/usual.c:161\n    #2 close_object            /ext/oj/usual.c:285\n    #3 parse                   /ext/oj/parser.c:693\n    #4 parser_parse            /ext/oj/parser.c:1408\nfreed by thread T0 here:\n    #0 free\n    #1 cache_free              /ext/oj/cache.c:277\n    #2 opt_symbol_keys_set     /ext/oj/usual.c:1051\n    #3 option                  /ext/oj/usual.c:1111\n    #4 parser_missing          /ext/oj/parser.c:1362\n0x50b00001a318 is 40 bytes inside freed 112-byte region [fd]fd fd fd fd fd fd fd\n```\n\n### Reproduce\n\n```ruby\nrequire 'oj'\np = Oj::Parser.new(:usual, symbol_keys: true)\np.symbol_keys = false     # frees cache without nulling pointer\np.parse('{\"attacker\":1}') # UAF: reads freed cache\n```","status":"published","published":"2026-06-19T19:34:30Z","modified":"2026-10-06T20:00:05.191640486Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T15:46:34.338541Z"},{"id":"UBUNTU-CVE-2026-54899","description":"Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to version 3.17.2, disabling symbol_keys on a reused Oj::Parser instance triggers a heap use-after-free. When symbol_keys is toggled from true to false, opt_symbol_keys_set frees the internal key cache (cache_free) but does not clear the pointer. The next parse call reads from the freed cache via cache_intern, producing a use-after-free. This issue has been fixed in version 3.17.2.","status":"published","published":"2026-07-01T00:16:00Z","modified":"2026-10-17T13:00:26.907629323Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T16:56:41.382716Z"}]}}