{"id":"CVE-2026-89312","kind":"vulnerability","aliases":["CVE-2026-89312"],"related":[],"title":"Go AES-GCM cryptor: wrong-sized nonce crashes the decrypting goroutine","description":"`AesGcmCryptor.Open` passed a caller-supplied nonce straight to `cipher.AEAD.Open` without checking its length. The Go standard library **panics** rather than returning an error when a GCM nonce is not exactly `NonceSize()` bytes, so a JWE carrying a wrong-sized IV crashes the decrypting goroutine.","summary":"AesGcmCryptor.Open passes a caller-supplied nonce to the Go AEAD Open call without checking its length. A JWE with a wrong-sized IV makes the standard library panic, which crashes the goroutine that decrypts it.","severity":"medium","cvss":6.9,"epss":0.00253,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["go","jwe","package","self-hosted"],"not_affected_if":["auth-not-using-aesgcm","no-untrusted-jwe"],"how_to_check":"- Check whether the project imports the library that defines `AesGcmCryptor` and calls `Open` on JWE input, for example with `go list -m all`\n- Confirm whether untrusted tokens or payloads reach that decrypt path","fix":null,"status":"open","published_at":"2026-10-23T09:17:07+00:00","first_seen_at":"2026-10-23T21:57:32+00:00","triaged_at":"2026-10-25T03:38:37+00:00","updated_at":"2026-10-25T03:38:37+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-10-25T03:38:37Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"network","title":"Go AES-GCM cryptor: wrong-sized nonce crashes the decrypting goroutine","impact":"low","summary":"AesGcmCryptor.Open passes a caller-supplied nonce to the Go AEAD Open call without checking its length. A JWE with a wrong-sized IV makes the standard library panic, which crashes the goroutine that decrypts it.","category":"package","nicknames":[],"who_cares":["go","jwe","self-hosted"],"confidence":0.6,"needs_auth":"unknown","worst_case":"Remote input crashes the decrypting service process, causing denial of service","analyst_note":"Find the fixed version and the affected library name from the NVD entry at https://nvd.nist.gov/vuln/detail/CVE-2026-89312.","how_to_check":"- Check whether the project imports the library that defines `AesGcmCryptor` and calls `Open` on JWE input, for example with `go list -m all`\n- Confirm whether untrusted tokens or payloads reach that decrypt path","needs_analyst":true,"not_affected_if":["no-untrusted-jwe","auth-not-using-aesgcm"],"who_is_affected":"Services that decrypt attacker-supplied JWE tokens with AesGcmCryptor.Open are exposed, because a malformed IV can crash the process. Systems that only decrypt data they produced themselves, or never call this cryptor, can skip it. The sources do not name a patched version.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000615,"input_tokens":3387,"output_tokens":552,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':15A,18A '-89312':16A,19A 'ae':3A 'aead':36B 'aes-gcm':2A 'aesgcmcryptor.open':26B,62C 'byte':94C 'call':38B 'caller':30B,66C 'caller-suppli':29B,65C 'carri':98C 'check':40B,73C 'cipher.aead.open':71C 'crash':10A,57B,104C 'cryptor':5A 'cve':14A,17A 'decrypt':12A,61B,106C 'error':85C 'exact':92C 'gcm':4A,88C 'go':1A,20B,35B,77C 'goroutin':13A,59B,107C 'host':25B 'iv':50B,103C 'jwe':21B,44B,97C 'length':42B,75C 'librari':54B,79C 'make':51B 'nonc':9A,32B,68C,89C 'nonces':93C 'open':37B 'packag':22B 'panic':55B,80C 'pass':27B,63C 'rather':81C 'return':83C 'self':24B 'self-host':23B 'size':8A,49B,102C 'standard':53B,78C 'straight':69C 'suppli':31B,67C 'without':39B,72C 'wrong':7A,48B,101C 'wrong-siz':6A,47B,100C","nicknames":[],"mitigations":[],"who_affected":"Services that decrypt attacker-supplied JWE tokens with AesGcmCryptor.Open are exposed, because a malformed IV can crash the process. Systems that only decrypt data they produced themselves, or never call this cryptor, can skip it. The sources do not name a patched version.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-23T09:17:07+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/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","cvss_by":"emo@eclipse.org","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-89312","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89312","severity":null,"published_at":"2026-10-23T09:17:07+00:00","modified_at":"2026-10-23T19:30:07+00:00","first_seen_at":"2026-10-23T21:57:32+00:00","fetched_at":"2026-10-23T22:29:03+00:00","note":null},{"source":"epss","external_id":"CVE-2026-89312","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-89312","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-24T07:15:51+00:00","fetched_at":"2026-10-24T07:15:51+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}