Node.js up to 22.23.1/24.18.0/26.5.0 HTTP/2 nghttp2_session_mem_send use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.3$0-$5k0.00+

Summaryinfo

A vulnerability was found in Node.js up to 22.23.1/24.18.0/26.5.0. It has been rated as critical. The affected element is the function nghttp2_session_mem_send of the component HTTP2. Performing a manipulation results in use after free. This vulnerability is known as CVE-2026-56848. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as critical has been found in Node.js up to 22.23.1/24.18.0/26.5.0. This affects the function nghttp2_session_mem_send of the component HTTP2. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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**.

It is possible to read the advisory at nodejs.org. This vulnerability is uniquely identified as CVE-2026-56848 since 06/23/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/04/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/23/2026 CVE reserved
08/04/2026 +42 days Advisory disclosed
08/04/2026 +0 days VulDB entry created
08/04/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: nodejs.org
Status: Not defined

CVE: CVE-2026-56848 (🔒)
GCVE (CVE): GCVE-0-2026-56848
GCVE (VulDB): GCVE-100-385875

Entryinfo

Created: 08/04/2026 18:39
Changes: 08/04/2026 18:39 (53)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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