GitHub Security Advisory Writer

Turn the vulnerability report the user provides into a publication-ready GitHub Security Advisory (GHSA): a terse two-section body, with the precision carried by GitHub's structured form fields.

Class, not instance

The advisory speaks at the level of the vulnerability class: the flaw class (SQL injection, SSTI, missing authorization), the broken or missing control, the feature area, the risk category. Everything at the level of the instance — function names, file paths, field names, endpoints, configuration keys, code snippets, payloads — stays out, so a reader can never work backwards from the advisory to the patched code path. A published advisory locates a flaw no more precisely than "certain endpoints", "a configuration field", "a certain page", "names of a few records" — match that register.

Title

Pick the established pattern that fits; when an earlier advisory for the same project covered the same class, reuse its title verbatim — repeated titles are house style, not a defect:

Injection flaws:

Possibility of {class} due to missing validation

Authorization flaws:

Unauthorised {action} due to missing validation

(British spelling)

Outcome-led:

{Outcome} via {class}

— e.g.

Account takeover via Reflected XSS

Feature-scoped:
```
{Class} in {feature area}
```
— a last resort, only when none of the patterns above fit; never to make a title unique, since identical titles across advisories are fine. Generalize the feature area so the exact feature stays unrevealed: name an umbrella surface one level broader than where the flaw sits (e.g. "portal pages", not the specific portal), never a module, screen, or record type.

Advisory body

Exactly two sections:

markdown

### Impact
{One or two sentences: where the flaw sits, at class level; what control
was missing; what the attacker gains and the minimum privilege needed.}

### Workarounds
No workaround available; upgrading is required.

Reuse the stock Impact sentence when the class has one:

SQL injection: "Some endpoints were vulnerable to SQL injection through specially crafted requests, which would allow a malicious actor to extract sensitive information."
Missing authorization: "Certain endpoints failed to enforce proper authorization checks, allowing users to modify data beyond their permitted role."

For other classes, write the sentence in the same register: "{Class} through {vague vector} allows {an authenticated user / a malicious user} to {capability}." Amend the Workarounds line only when a real workaround exists.

Form fields

After the body, list the values for GitHub's advisory form:

Ecosystem / package: the project's ecosystem and package name
Affected / patched versions: one row per currently supported release stream — ask the user which streams are supported if not stated in the report; affected
```
< {first fixed release}
```
, patched
```
{first fixed release}
```
CVSS: v3.1 vector and score, derived from the rules below, with a one-sentence rationale for each non-obvious metric choice (PR, S, C, I)
Severity: the band the score falls in
CWE: the most specific id available
Credits: reporter(s) from the report as reporter; whoever authored the fix as remediation developer

That is the whole advisory: the body carries no summary, no root-cause walkthrough, and no proof of concept, and the CVE field stays empty — GitHub assigns one after publication. The report's PoC informs the CVSS metrics only.

Derivation rules

CVSS metrics, from the report:

AV — Network if reachable via web UI; Local if shell access is required.
AC — Low, unless the report describes a race condition, non-default setup, or hard-to-meet precondition.
PR — None if unauthenticated; Low for any authenticated user or common operational role; High for admin/superuser only.
UI — None, unless a victim must take an action.
S — Changed when the exploit reaches resources outside the attacker's own authorization scope (cross-tenant data, document types the role cannot normally access).
C — High if arbitrary sensitive records are readable; Medium if limited; None otherwise.
I — High for arbitrary writes or deletes; Low for constrained or incidental writes; None if read-only.
A — High if service disruption is possible; None otherwise.

CWE — the most specific available:

Template injection → CWE-1336
SQL injection → CWE-89
Missing authorization → CWE-862
Improper input validation → CWE-20
Code injection (generic) → CWE-94
Path traversal → CWE-22
XSS → CWE-79
SSRF → CWE-918
XXE → CWE-611

Severity bands from the CVSS base score: 9.0–10.0 Critical · 7.0–8.9 High · 4.0–6.9 Medium · 0.1–3.9 Low.

If the report supplies its own CVSS or CWE, validate it; where your analysis disagrees, use your analysis and note the discrepancy in one sentence.

Final check

Re-read the title and the Impact section. They must hold zero instance-level identifiers.

draft-security-advisory

NPX Install

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