How severe is CVE-2026-40879?

CVE-2026-40879 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-40879 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-40879?

CVE-2026-40879 affects Nestjs Nest. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-40879?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-40879 have an EU (EUVD) identifier?

Yes. CVE-2026-40879 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24264.

When was CVE-2026-40879 published?

CVE-2026-40879 was published on 2026-04-21 and last updated on 2026-06-17.

CVE-2026-40879

CVE-2026-40879 is a high-severity vulnerability in Nestjs Nest with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-674.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-24264
Weakness: CWE-674
Affected product: Nestjs Nest
Published: 2026-04-21
Last modified: 2026-06-17

Description

Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.19, when an attacker sends many small, valid JSON messages in one TCP frame, handleData() recurses once per message; the buffer shrinks each call. maxBufferSize is never reached; call stack overflows instead. A ~47 KB payload is sufficient to trigger RangeError. This vulnerability is fixed in 11.1.19.

Frequently asked questions

What is CVE-2026-40879?: Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.19, when an attacker sends many small, valid JSON messages in one TCP frame, handleData() recurses once per message; the buffer shrinks each call. maxBufferSize is never reached; call stack overflows instead. A ~47 KB payload is sufficient to trigger RangeError. This vulnerability is fixed in 11.1.19.
How severe is CVE-2026-40879?: CVE-2026-40879 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-40879 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-40879?: CVE-2026-40879 affects Nestjs Nest. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-40879?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-40879 have an EU (EUVD) identifier?: Yes. CVE-2026-40879 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24264.
When was CVE-2026-40879 published?: CVE-2026-40879 was published on 2026-04-21 and last updated on 2026-06-17.

References

https://github.com/nestjs/nest/security/advisories/GHSA-hpwf-8g29-85qm

Affected products (1)

cpe:2.3:a:nestjs:nest:*:*:*:*:*:node.js:*:*

More vulnerabilities in Nestjs Nest

CVE-2026-2293 — Critical (CVSS 9.8): A NestJS application using @nestjs/platform-fastify can allow bypass of authentication/authorization middleware when…
CVE-2026-33011 — High (CVSS 7.5): Nest is a framework for building scalable Node.js server-side applications. In versions 11.1.15 and below, a NestJS…
CVE-2025-69211 — High (CVSS 7.4): Nest is a framework for building scalable Node.js server-side applications. Versions prior to 11.1.11 have a Fastify…
CVE-2026-35515 — Medium (CVSS 6.1): Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.18, SseStream._transform()…
CVE-2024-29409 — Medium (CVSS 5.5): File Upload vulnerability in nestjs nest v.10.3.2 allows a remote attacker to execute arbitrary code via the…
CVE-2023-26108 — Low (CVSS 3.7): Versions of the package @nestjs/core before 9.0.5 are vulnerable to Information Exposure via the StreamableFile pipe.…

All CVEs affecting Nestjs Nest →

Other CWE-674 (Uncontrolled Recursion) vulnerabilities

CVE-2026-43185 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix signededness bug in…
CVE-2023-51803 — Critical (CVSS 9.8): LinuxServer.io Heimdall before 2.5.7 does not prevent use of icons that have non-image data such as the "<?php ?>"…
CVE-2021-41752 — Critical (CVSS 9.8): Stack overflow vulnerability in Jerryscript before commit e1ce7dd7271288be8c0c8136eea9107df73a8ce2 on Oct 20, 2021 due…
CVE-2018-1000618 — Critical (CVSS 9.8): EOSIO/eos eos version after commit f1545dd0ae2b77580c2236fdb70ae7138d2c7168 contains a stack overflow vulnerability in…
CVE-2025-10728 — Critical (CVSS 9.4): When the module renders a Svg file that contains a <pattern> element, it might end up rendering it recursively leading…
CVE-2026-40324 — Critical (CVSS 9.1): Hot Chocolate is an open-source GraphQL server. Prior to versions 12.22.7, 13.9.16, 14.3.1, and 15.1.14, Hot…

Browse all CWE-674 (Uncontrolled Recursion) vulnerabilities →