CVE-2026-104845 Seroval: Memory exhaustion via unchecked TypedArray length in JSON deserialization
An attacker can cause memory exhaustion and denial of service in Seroval by providing a crafted JSON object with a large length value during deserialization.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-104845?
CVE-2026-104845 is a high-severity denial of service vulnerability in lxsmnsyc seroval, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. Prior to 1.6.3, deserializeTypedArray in fromJSON and fromCrossJSON trusts a deserialized source value as an ArrayBuffer and does not bound the serialized element count. An attacker can provide a small untrusted JSON object with a large length value, causing the array-like TypedArray constructor to synchronously allocate the selected number of elements and exhaust CPU or memory while starving the event loop. The offset check does not reject the crafted source because source.byteLength is undefined. DataView reaches a similar unchecked cast but throws rather than allocating, and the issue has no identified confidentiality or integrity impact. This issue is fixed in version 1.6.3.
Weakness: CWE-770
Which versions are affected by CVE-2026-104845?
2 open source packages ship an affected version, including seroval.
| Package | Affected | Fixed in |
|---|---|---|
seroval npm | All versions | 1.6.3 |
seroval npm | All versions | 1.6.3 |
How do I fix CVE-2026-104845?
Upgrade seroval to 1.6.3 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-104845 being exploited?
There is no known exploitation of CVE-2026-104845 in the wild and no public exploit code.
Sources
Also known as CLSA-2026-1791289714, CLSA-2026-1792286817, GHSA-jp82-f5mq-hwhp.