# CVE-2024-33600: GNU glibc null pointer dereference in nscd netgroup cache

Source: https://junglewise.ai/threats/cve-2024-33600-gnu-glibc-null-pointer-dereference-in-nscd-netgroup-cache  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2024-05-06. Updated: 2026-05-12  
License: CC BY 4.0 with a link back

CVE-2024-33600 · Severity: medium · CVSS 5.9 · Published 2024-05-06

A vulnerability in the GNU C Library's Name Service Cache Daemon (nscd) can cause the service to crash. This component is responsible for speeding up network-related lookups like user and group information. If exploited, an attacker could cause a denial-of-service, disrupting system operations and network authentication services.

Technologies: [Debian Linux](https://junglewise.ai/threats/technologies/debian), [Gnu Glibc](https://junglewise.ai/threats/technologies/glibc), [NetApp H300s](https://junglewise.ai/threats/technologies/h300s), [NetApp H300s Firmware](https://junglewise.ai/threats/technologies/h300s-firmware), [NetApp H410c](https://junglewise.ai/threats/technologies/h410c), [NetApp H410c Firmware](https://junglewise.ai/threats/technologies/h410c-firmware), [NetApp H410s](https://junglewise.ai/threats/technologies/h410s), [NetApp H410s Firmware](https://junglewise.ai/threats/technologies/h410s-firmware), [NetApp H500s](https://junglewise.ai/threats/technologies/h500s), [NetApp H500s Firmware](https://junglewise.ai/threats/technologies/h500s-firmware), [NetApp H700s](https://junglewise.ai/threats/technologies/h700s), [NetApp H700s Firmware](https://junglewise.ai/threats/technologies/h700s-firmware), [NetApp Hci Bootstrap Os](https://junglewise.ai/threats/technologies/hci-bootstrap-os), [Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP](https://junglewise.ai/threats/technologies/simatic-s7-1500-cpu-1518-4-pn-dp-mfp). Vendors: [Debian](https://junglewise.ai/threats/vendors/debian), [Gnu](https://junglewise.ai/threats/vendors/gnu), [NetApp](https://junglewise.ai/threats/vendors/netapp), [Siemens](https://junglewise.ai/threats/vendors/siemens).

## Quick answers

**Is CVE-2024-33600 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2024-33600 being exploited in the wild.

**How severe is CVE-2024-33600?** Medium severity, with a CVSS score of 5.9, published 6 May 2024.

**Which products and versions are affected?** Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP >= V3.1.5.

**Is there a fix for CVE-2024-33600?** A patch was published on 2024-06-30: Debian LTS update released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2024-33600 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2024-33600?** Check whether you run Debian Linux, Gnu Glibc, NetApp Active Iq Unified Manager or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A null pointer dereference vulnerability exists in the nscd binary of glibc. The flaw occurs when the daemon's cache fails to add a 'not-found' netgroup response to its internal cache. A subsequent client request for that same netgroup can trigger the dereference, resulting in a crash of the nscd process. This issue was introduced in glibc 2.15 and affects versions up to 2.39. While the attack vector is network-based, it requires a high complexity (AC:H) to trigger the specific cache failure state. Patches are available in glibc 2.40 and various backported stable releases.

## Affected products

- GNU glibc 2.15 to 2.39
- Debian Debian Linux 10.0
- Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP >= V3.1.5

## Timeline

- 2024-04-24: disclosed: Public date listed in glibc advisory
- 2024-05-06: advisory: NVD publication date
- 2024-06-30: patched: Debian LTS update released
- 2024-07-22: patched: glibc 2.40 released with fix

## References

- [http://www.openwall.com/lists/oss-security/2024/07/22/5](http://www.openwall.com/lists/oss-security/2024/07/22/5)
- [https://lists.debian.org/debian-lts-announce/2024/06/msg00026.html](https://lists.debian.org/debian-lts-announce/2024/06/msg00026.html)
- [https://security.netapp.com/advisory/ntap-20240524-0013/](https://security.netapp.com/advisory/ntap-20240524-0013/)
- [https://sourceware.org/git/?p=glibc.git;a=blob;f=advisories/GLIBC-SA-2024-0006](https://sourceware.org/git/?p=glibc.git;a=blob;f=advisories/GLIBC-SA-2024-0006)
- [https://cert-portal.siemens.com/productcert/html/ssa-082556.html](https://cert-portal.siemens.com/productcert/html/ssa-082556.html)

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