vulnerability / NVI-00013093 / Revision 1
Nodemailer: Quadratic backtracking in the addressparser free-text fallback allows remote denial of service
GitHub lists this reviewed advisory for nodemailer. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
7.5 high
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
nodemailer
source listed<= 10.0.5
### Summary When `addressparser` finds no address by its strict reading, it falls back to pulling one out of the free text with `/\s*\b[^@\s]+@[^\s]+\b\s*/`. That pattern backtracks quadratically: `[^@\s]+` is retried from every offset and rescans the run to the next `@` each time. A single header value holding a long whitespace-free run with no usable `@` blocks the Node.js event loop for tens of seconds. It is cheaper to exploit than GHSA-prgh-xp8r-p3m5: 273KB is enough for ~43s, where the comment-joined shape needed ~1.5MB for ~10s. ### Details The fallback in `src/addressparser/index.ts` ran the pattern as a search. `[^@\s]+` crosses neither whitespace nor `@`, so from each start offset it scans forward to the next `@` or to the end of the run and then fails, and the engine simply advances one character and repeats. Three shapes make every offset fail: - the run holds no `@` at all - the only `@` has nothing after it - the only `@` has nothing before it A fourth reaches it with a valid address present but placed past a long run, so the long run is walked before the match is found. ### PoC ```js const addressparser = require('nodemailer/lib/addressparser'); const s = Dat
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-v53p-9fqp-m79j ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.