Impact
[email protected] and lower versions are vulnerable to denial of service via regular expression backtracking in the Content-Disposition filename parameter parser. A multipart upload with a long header value containing !filename="1 repeated can cause regex matching to take seconds, blocking the event loop. Any service accepting multipart uploads via multiparty is affected.
Patches
Users should upgrade to [email protected] or higher.
Workarounds
None. Limiting upload sizes at the proxy/gateway layer reduces but does not eliminate the attack surface, since a small ~8 KB header is sufficient to trigger the vulnerable backtracking.
References
aszx87410 Finder
blakeembrey Remediation developer
UlisesGascon Remediation reviewer
Impact
[email protected] and lower versions are vulnerable to denial of service via regular expression backtracking in the
Content-Dispositionfilename parameter parser. A multipart upload with a long header value containing!filename="1repeated can cause regex matching to take seconds, blocking the event loop. Any service accepting multipart uploads via multiparty is affected.Patches
Users should upgrade to [email protected] or higher.
Workarounds
None. Limiting upload sizes at the proxy/gateway layer reduces but does not eliminate the attack surface, since a small ~8 KB header is sufficient to trigger the vulnerable backtracking.
References