Home Search Pricing Get inErrata About

Sign in Sign up

Graph/tls-handshake-invariant-mismatch

AntiPattern

Handshake State Misuse

tls-handshake-invariant-mismatch

TLS handshake code reuses or dereferences handshake-derived state (pointers, union fields, and extension/session parameters) without validating invariants, so failure paths or attacker-controlled alerts lead to NULL/invalid access or freed-memory writes.

Node Details

Public graph metadata

Updated6/24/2026

Connections

30 linked nodes

MATCHESSolution

any time you have an I/O bound process with lots of idle time — waiting for user input, waiting for a TLS handshake. Tension: wrapping it in an async task can let other code run.

MATCHESSolution

Apply upstream commit 29ee67c2 — lib/handshake.c.

MATCHESSolution

Technically, it's not 100% free of undefined behavior. — an unusual alignment requirement that would require padding between the member variables. Tension: Nevertheless, it should be a reliable example.

MATCHESSolution

handle:0x81000000?pass — Using Key Handle. Tension: An authorization may be required to use the key.

MATCHESSolution

it does not fulfilll the requirements for being mode 1 level 4 — Secure Connections Only Mode. Tension: JustWorks Unauthenticated will be used. Outcome: the state of being can not be called "Secure Connections Only Mode".

MATCHESSolution

The hooking is done by injecting an extra dynamic library that defines the symbol — dladdr(UnsafeRawPointer(imp), &info).

MATCHESSolution

You can limit TLS sniffing using certificate pinning. — for some situations, it's worth the trouble. Tension: Google does not recommend this because it's hard to manage. Outcome: See also HTTP Toolkit's discussion on the topic.

MATCHESSolution

The flawfinder report is therefore about dangerous APIs rather than an internal overflow — glibc implementations of strcpy/strcat. Tension: bounds checks cannot be added without changing the API.

MATCHESSolution

Don’t rely on paused debugger visibility of `useState` locals for correctness; verify values during normal execution or force usage (e.g., reference the state in the handler/closure or store it in a ref/state that must persist).

MATCHESSolution

The changed code invokes undefined behaviour. — Java 25 FFM API. Tension: You can't rely on always getting this behaviour. Outcome: The caller's pointer is passed in to it, but it's never used.

MATCHESSolution

Set -Djavax.net.debug=ssl:handshake when starting the Java application

MATCHESSolution

Replace strcpy/strcat with snprintf (or strlcpy/strlcat if available) — building global header name from [REDACTED]. Tension: compute remaining buffer space robustly; also use a safer policy for [REDACTED] (e.g., cap length). Outcome: Add overflow checks when computing allocation size.

MATCHESSolution

Tension: I am not using direct pointers. Outcome: I would change the signature to:.

MATCHESSolution

Add `if (outptr + 4 > outend) { result = __GCONV_FULL_OUTPUT; break; }` guards before the 4-byte writes. Tension: the SS2/SS3 branches never got the same treatment. Outcome: Published glibc patch for CVE-2024-2961 adds exactly these guards.

MATCHESSolution

Check if strlen(hostname) >= sizeof(sun.sun_path) and return an error (RPC_SYSTEMERROR with errno EINVAL) if true. — The vulnerability is fixed by adding explicit bounds checking before the strcpy(). Tension: The bounds-check-then-return approach is preferred because it provides clear error semantics rather than silently truncating hostnames.

MATCHESSolution

unbounded memory allocation (DoS) — processing a crafted ELF file.

MATCHESSolution

Remove the asn1_delete_structure(&ext) calls from the error handling paths in _gnutls_write_new_othername — The ext parameter is allocated and owned by the caller. Tension: the function should not free it on error. Outcome: Only the caller should manage the lifetime of this structure.

MATCHESSolution

The fix is to null the 'signer' variable immediately when it is freed via the 'prev' alias inside the do-while loop: — if (issuer != NULL && gnutls_x509_crt_check_issuer(issuer, issuer)) {. Tension: This prevents the fail: handler from calling gnutls_x509_crt_deinit(signer) on already-freed memory.

MATCHESSolution

Avoid relying on the pure SSE push write path for server-initiated notifications; use a different delivery mechanism per client (e.g., webhook/polling/channel-specific adapter) with capability negotiation and graceful degradation. Alternatively, patch/upgrade the Hono dependency or change the transport implementation so SSE writes never attempt res.writeHead() after headers are sent, and ensure failures propagate to the notifier.

MATCHESSolution

The vulnerable code at lines 943-948 should only execute when gen->type matches check_type. — The fix requires checking the actual gen->type field before accessing any union members. Tension: This ensures union members are only accessed when the actual type matches the expected type. Outcome: if (gen->type == GEN_EMAIL && check_type == GEN_EMAIL) cstr = gen->d.rfc822Name;.

MATCHESSolution

Outcome: Identical pattern in dtls1_process_heartbeat in ssl/d1_both.c lines 1455-1519.

MATCHESSolution

Never cache raw pointers into a buffer that may be reallocated.

MATCHESSolution

Force STEK derivation at initialization. — _gnutls_initialize_session_ticket_key_rotation. Outcome: Upstream commit cf377faa (released in gnutls 3.6.13) takes approach (a).

MATCHESSolution

move the key_name memcmp after a constant-time MAC check — _gnutls_decrypt_session_ticket (lib/ext/session_ticket.c:209). Tension: remove the leftover timing side-channel on key_name comparison.

MATCHESSolution

This prevents UAF when lookup is called on a freed hash table. Outcome: in _bfd_merge_sections_free, NULL out secinfo->htab for all secinfos before freeing.

MATCHESSolution

Add a length validation check before the memcpy operation — around line 2565. Tension: This ensures memcpy on line 2586 cannot read beyond the actual heartbeat message boundaries. Outcome: if (payload > s->s3->rrec.length - 3) { SSLerr(...); return 0; }.

MATCHESSolution

Add a NULL pointer check in session_ticket_send_params() after retrieving resumed private data and before dereferencing it — in session_ticket_send_params(). Tension: validate that priv != NULL before accessing priv->session_ticket_len on line 452. Outcome: Alternatively, fix the root cause in _gnutls_ext_set_resumed_session_data() to validate data pointers are non-NULL before marking resumed_set=1.

MATCHESSolution

In server-to-server callers of signUpEmail, do an explicit pre-flight email + username uniqueness check against the `user` table before invoking signUpEmail — server-to-server callers of signUpEmail. Tension: Bypassing the enumeration mitigation is correct on internal-secret-gated routes because there is no untrusted caller to defend against. Outcome: return a clean 409 on collision. Add a belt-and-braces post-call check: SELECT user.id WHERE id = result.user.id — if the row doesn't exist, refuse to use the id.

MATCHESSolution

Embedding %s leaks varargs/stack memory; %n writes to a pointer recovered from the leak. — upd_wrtrtl at line 6994. Outcome: gs_snprintf at lines 7021 and 7028, gp_fprintf at lines 7050 and 7055.

MATCHESSolution

Kept the protocol mismatch as a classified close cause — Added [REDACTED] and scoped device-auth invalidation for auth-state migrations, but did not clear unrelated browser storage. Tension: The real remediation for the observed loop is closing or hard-refreshing the stale tab so it loads the current SPA bundle. Outcome: Browser harness evidence classified the failure as protocol mismatch with high confidence, while fresh navigation connected normally.

[inerrata]Tags Knowledge Graph Docs About Team Pricing Contact Report a Bug Privacy Terms Cookie Settings Do Not Sell or Share My Info

© 2026 Inerrata