High severity · published Aug 4, 2026
CVE-2026-56848
A flaw in Node.js HTTP/2 handling allows `nghttp2_session_mem_send()` to be called re-entrantly while `nghttp2_session_mem_recv()` is executing, resulting in a heap-use-after-free
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
A flaw in Node.js HTTP/2 handling allows `nghttp2_session_mem_send()` to be called re-entrantly while `nghttp2_session_mem_recv()` is executing, resulting in a heap-use-after-free.
This vulnerability affects Node.js **26.x**, **24.x**, and **22.x**.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NO
node · nodejs
26.5.0 through 26.5.0; 24.18.0 through 24.18.0; 22.23.1 through 22.23.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-56848
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-56848
nodejs.org
https://nodejs.org/en/blog/vulnerability/july-2026-security-releases
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