CVE-2016-10544
Denial of Service in uws
uws is a WebSocket server library. By sending a 256mb websocket message to a uws server instance with permessage-deflate enabled, there is a possibility used compression will shrink said 256mb down to less than 16mb of websocket payload which passes the length check of 16mb payload. This data will then inflate up to 256mb and crash the node process by exceeding V8's maximum string size. This affects uws >=0.10.0 <=0.10.8.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
uws is a WebSocket server library. By sending a 256mb websocket message to a uws server instance with permessage-deflate enabled, there is a possibility used compression will shrink said 256mb down to less than 16mb of websocket payload which passes the length check of 16mb payload. This data will then inflate up to 256mb and crash the node process by exceeding V8's maximum string size. This affects uws >=0.10.0 <=0.10.8.
- Record
CVE-2016-10544- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:N/A:P - Weakness
- CWE-400, CWE-20
- Updated
- 2026-11-02
CVE List No score
uws is a WebSocket server library. By sending a 256mb websocket message to a uws server instance with permessage-deflate enabled, there is a possibility used compression will shrink said 256mb down to less than 16mb of websocket payload which passes the length check of 16mb payload. This data will then inflate up to 256mb and crash the node process by exceeding V8's maximum string size. This affects uws >=0.10.0 <=0.10.8.
- Record
CVE-2016-10544- Weakness
- CWE-400
- Updated
- 2026-11-02
EUVDEUVD-2020-1096 No score
uws is a WebSocket server library. By sending a 256mb websocket message to a uws server instance with permessage-deflate enabled, there is a possibility used compression will shrink said 256mb down to less than 16mb of websocket payload which passes the length check of 16mb payload. This data will then inflate up to 256mb and crash the node process by exceeding V8's maximum string size. This affects uws >=0.10.0 <=0.10.8.
- Record
EUVD-2020-1096- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-hf5h-hh56-3vrg No score
Denial of Service in uws
Affected versions of uws do not properly handle large websocket messages when permessage-deflate is enabled, which may result in a denial of service condition.
If uws recieves a 256Mb websocket message when permessage-deflate is enabled, the server will compress the message prior to executing the length check, and subsequently extract the message prior to processing. This can result in a situation where an excessively large websocket message passes the length checks, yet still gets cast from a Buffer to a string, which will exceed v8's maximum string size and crash the process.
Recommendation
Update to version 0.10.9 or later.
Alternatively, disable permessage-deflate.
- Record
GHSA-hf5h-hh56-3vrg- Weakness
- CWE-400
- Updated
- 2026-11-02
OSV
uws is a WebSocket server library. By sending a 256mb websocket message to a uws server instance with permessage-deflate enabled, there is a possibility used compression will shrink said 256mb down to less than 16mb of websocket payload which passes the length check of 16mb payload. This data will then inflate up to 256mb and crash the node process by exceeding V8's maximum string size. This affects uws >=0.10.0 <=0.10.8.
- Record
CVE-2016-10544- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVGHSA-hf5h-hh56-3vrg No score
Denial of Service in uws
Affected versions of uws do not properly handle large websocket messages when permessage-deflate is enabled, which may result in a denial of service condition.
If uws recieves a 256Mb websocket message when permessage-deflate is enabled, the server will compress the message prior to executing the length check, and subsequently extract the message prior to processing. This can result in a situation where an excessively large websocket message passes the length checks, yet still gets cast from a Buffer to a string, which will exceed v8's maximum string size and crash the process.
Recommendation
Update to version 0.10.9 or later.
Alternatively, disable permessage-deflate.
- Record
GHSA-hf5h-hh56-3vrg- Weakness
- CWE-400
- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2016-10544 is a medium vulnerability (CVSS 5.9) in Uws Project Uws, published May 31, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.32%, the 70th percentile. Fixed in uws 0.10.9.