# CVE-2026-104593: osmo-msc stack-based buffer overflow in decode_mme_name()

Source: https://junglewise.ai/threats/cve-2026-104593-osmo-msc-through-1-15-0-contains-a-stack-based-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-26. Updated: 2026-10-26  
License: CC BY 4.0 with a link back

CVE-2026-104593 · Severity: info · Published 2026-10-26

osmo-msc is a mobile switching center component used in cellular network infrastructure. A remote attacker can send a specially crafted message with an oversized MME name field to trigger a stack-based buffer overflow, causing the service to crash and disrupting network connectivity for users served by that switch.

Vendors: [Osmocom](https://junglewise.ai/threats/vendors/osmocom).

## Quick answers

**Is CVE-2026-104593 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-104593 being exploited in the wild.

**How severe is CVE-2026-104593?** Informational severity, published 26 October 2026.

**Which products and versions are affected?** Osmocom Osmo-Msc through 1.15.0.

**Is there a fix for CVE-2026-104593?** Yes: fixed in Patched in osmo-msc commit cd347bb (which adds length validation to decode_mme_name function). Until then: Restrict network access to trusted peers and monitor MME name information element sizes in network traffic. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-104593 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-104593?** Check whether you run Osmocom Osmo-Msc 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.

## How to fix

- Fixed in Patched in osmo-msc commit cd347bb (which adds length validation to decode_mme_name function)

Restrict network access to trusted peers and monitor MME name information element sizes in network traffic.

## Technical details

The decode_mme_name() function in src/libmsc/sgs_iface.c fails to validate the length of the MME name information element before copying it into a fixed-size stack buffer. An attacker on the network can craft an SGSAP_IE_MME_NAME message longer than SGS_MME_NAME_LEN to overflow the buffer, either directly via memcpy or through osmo_apn_to_str(), resulting in denial of service via crash.

## Affected products

- osmocom osmo-msc through 1.15.0

## Timeline

- 2026-10-26: disclosed
- 2026-10-26: patched: Fix available in commit cd347bb

## References

- [https://github.com/osmocom/osmo-msc/commit/cd347bbe5392d8170ab87140b2bfdac683058b09](https://github.com/osmocom/osmo-msc/commit/cd347bbe5392d8170ab87140b2bfdac683058b09)
- [https://osmocom.org/issues/7058](https://osmocom.org/issues/7058)