hunt-session

## Autonomous Testing Priority

**Missing HttpOnly on cookies is auto-detected — focus your active testing on lifecycle invalidation (higher impact).**

**Pattern 1 — Session survives logout (most common high-value finding):**
1. Login and note the session token/cookie value
2. Call the logout endpoint (`/logout`, `POST /api/logout`, etc.)
3. Try to use the OLD session token to access a protected resource (`/api/me`, `/dashboard`, `/account`)
4. If 200 with user data → session not invalidated on logout = ATO persistence

**Pattern 2 — Session not regenerated on login (session fixation):**
1. GET any page to receive a pre-authentication session token/cookie
2. POST valid credentials to the login endpoint
3. Compare the session token BEFORE and AFTER login
4. If the token is unchanged → session fixation vulnerability

**Pattern 3 — Session survives password change:**
1. Login → record session A value
2. Change the password via the account settings endpoint
3. Replay session A on a protected endpoint
4. If 200 → token not rotated on credential change = persistent ATO (critical chain when combined with XSS/cookie theft)

**Content-type:** Login and session endpoints vary — use `application/json` for REST APIs, `application/x-www-form-urlencoded` for traditional web forms. Try both if the first returns an unexpected response.

**Proof:** A protected-resource 200 response (with user data) using a session token that should have been invalidated confirms the finding.

---

# HUNT-SESSION — Session Management

## Crown Jewel Targets

Session fixation leading to admin hijack = Critical. Session surviving a password change = High-to-Critical (persistent ATO from a stolen cookie that the victim believes they revoked by resetting their password).

**Highest-value chains:**
- **Session fixation** — server accepts a session ID set by the client and does NOT regenerate it on login → attacker pre-plants an ID, victim authenticates, attacker rides the now-authenticated session → persistent ATO.
- **No invalidation on logout** — old token still works after `/logout` → theft window never closes.
- **No invalidation on password / email change** — a stolen session survives the victim's "I think I was hacked, let me reset" → persistent ATO. This is the single highest-paid session bug class.
- **Refresh-token reuse without rotation-detection** — a leaked refresh token mints fresh access tokens forever; no reuse-detection means the legitimate user's later refresh does NOT revoke the attacker's branch.
- **Predictable / low-entropy session ID** — sequential, timestamp- or userId-derived IDs → brute-force or compute other users' sessions.
- **JWT-as-session with no `exp` / no revocation list** — stolen JWT = permanent access; logout is cosmetic.

---

## Grounding — patterns that shaped each phase

No invented CVE/report IDs below. These are the *named, publicly-documented* patterns this skill encodes:

- **Session fixation, login-CSRF, no-regeneration-on-auth** — OWASP WSTG-SESS-03 / WSTG-SESS-01; the classic ACROS / Mitja Kolšek session-fixation paper. Highest-impact variant: fixing the session of an SSO/admin user.
- **SameSite=Lax sibling-subdomain CSRF reaching session state** — Argo CD **CVE-2024-22424** (Lax cookies sent on top-level cross-site navigations from a sibling subdomain). Use this when a session cookie relies on `SameSite=Lax` as its only CSRF defence.
- **Refresh-token rotation & automatic reuse-detection** — the Auth0/IETF OAuth-Security-BCP model: a rotated refresh token, if replayed, must invalidate the *entire token family*. Absence = the core bug to prove.
- **Device Bound Session Credentials (DBSC)** — the W3C/Chrome DBSC draft binds a session to a TPM/device key. Test the *downgrade*: does the server still accept a non-bound cookie when the DBSC challenge is stripped?
- **Cookie attribute hardening** — OWASP WSTG-SESS-02; `__Host-`/`__Secure-` prefixes per RFC 6265bis. Missing `HttpOnly` is only a finding when a real XSS/DOM sink exists (chain with `hunt-xss`/`hunt-dom`).
- **Entropy** — NIST SP 800-63B requires ≥64 bits of entropy in a session identifier. Treat anything decodable to a counter/timestamp/userId as a finding regardless of length.

Cross-refs: ATO chaining → `hunt-ato`; JWT alg/kid tampering → `hunt-api-misconfig`; OAuth code/state flaws → `hunt-oauth`; CSRF mechanics → `hunt-csrf`; cookie-theft sinks → `hunt-xss` / `hunt-dom`.

---

## Attack Surface Signals

```
Set-Cookie: session=...            # name varies: sid, JSESSIONID, connect.sid,
                                   # PHPSESSID, ASP.NET_SessionId, laravel_session, _csrf
/login /logout /api/login /oauth/token
/auth/refresh /api/token/refresh   # refresh-token rotation surface
/account/change-password /settings/email
?sid= ?session= in URL             # session-in-URL → leaks via Referer/logs (finding)
```
```
# Header signals worth flagging immediately:
Set-Cookie: session=abc; Path=/                 # no HttpOnly/Secure/SameSite
Set-Cookie: session=abc; SameSite=None          # None without Secure = rejected by modern browsers, but flag
Set-Cookie: __Host-sess=...; Secure; Path=/     # GOOD — hard to fixate
Sec-Session-Registration: ...                   # DBSC in play → test downgrade
```

---

## Step-by-Step Hunting Methodology

> **Two-session rule.** Every invalidation/fixation claim is proven with TWO concrete sessions captured by a real flow — attacker **A** and victim **B** — never with hardcoded placeholder strings. Helpers below capture real cookies from `curl`'s Netscape jar.

```bash
TARGET=target.com
JAR_A=$(mktemp); JAR_B=$(mktemp)

# Robust session-cookie extractor: handles #HttpOnly_ prefix lines and any
# cookie name (sid/JSESSIONID/connect.sid/PHPSESSID/...). Prints name=value.
get_cookie () {  # $1=jar  $2=name-regex (default: common session names)
  local jar="$1" re="${2:-session|sid|sess|JSESSIONID|connect\.sid|PHPSESSID|laravel_session}"
  awk -v re="$re" '
    /^#HttpOnly_/ { sub(/^#HttpOn