# CVE-2025-5517: ABB Terra AC heap-based buffer overflow in OCPP message handling

Source: https://junglewise.ai/threats/cve-2025-5517-abb-terra-ac-heap-based-buffer-overflow-in-ocpp-message-handling  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-10-20. Updated: 2026-05-26  
License: CC BY 4.0 with a link back

CVE-2025-5517 · Severity: high · CVSS 6.8 · Published 2025-10-20

ABB Terra AC wallboxes, which are Level 2 Electric Vehicle (EV) chargers, are affected by a memory vulnerability. An attacker who manages to compromise the charging management system or intercept unencrypted communications could take remote control of the charger. This could lead to the charger operating in an unpredictable mode, suffering a service outage, or having its internal firmware altered.

Vendors: [ABB](https://junglewise.ai/threats/vendors/abb).

## Quick answers

**Is CVE-2025-5517 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-5517 being exploited in the wild.

**How severe is CVE-2025-5517?** High severity, with a CVSS score of 6.8, published 20 October 2025.

**Which products and versions are affected?** ABB Terra AC Wallbox (JP) <=1.8.2; ABB Terra AC wallbox (MID/ CE) <=1.8.32; ABB Terra AC wallbox (UL32A) <=1.8.2; ABB Terra AC wallbox (UL40/80A) <=1.8.32.

**Is there a fix for CVE-2025-5517?** A patch was published on 2026-05-26: Firmware updates released for affected models Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-5517 attacked?** It is attacked over the network, in device firmware.

**Am I affected by CVE-2025-5517?** Check whether you run ABB Terra AC Wallbox (JP), ABB Terra AC wallbox (MID/ CE), ABB Terra AC wallbox (UL32A) 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 heap-based buffer overflow (CWE-122) exists in ABB Terra AC wallbox firmware due to insufficient length validation of OCPP (Open Charge Point Protocol) fields. An attacker can exploit this by sending a specially crafted OCPP message to the charger. This requires the attacker to either hijack the Charging Station Management System (CSMS) or intercept unencrypted HTTP communication between the charger and the backend. Successful exploitation can lead to memory pollution, denial-of-service, or remote code execution, potentially allowing the attacker to perform write operations to flash memory and alter firmware. Fixed versions include 1.8.33 for UL40/80A and PTB models, and 1.8.34 for UL32A, MID, Juno CE, and JP models.

## Affected products

- ABB Terra AC wallbox (UL40/80A) <=1.8.32
- ABB Terra AC wallbox (UL32A) <=1.8.2
- ABB Terra AC wallbox (MID/ CE) <=1.8.32
- ABB Terra AC wallbox (JP) <=1.8.2

## Timeline

- 2026-05-26: advisory: CISA Advisory ICSA-26-146-01 published
- 2026-05-26: patched: Firmware updates released for affected models

## References

- [https://www.cisa.gov/news-events/ics-advisories/icsa-26-146-01](https://www.cisa.gov/news-events/ics-advisories/icsa-26-146-01)

## Related threats

- [ABB Terra AC Wallbox multiple buffer overflows](https://junglewise.ai/threats/cve-2025-10504-abb-terra-ac-wallbox-multiple-buffer-overflows)