Quick answers
- Is CVE-2026-48706 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-48706 being exploited in the wild.
- How severe is CVE-2026-48706?
- Medium severity, with a CVSS score of 5.9, published 26 June 2026.
- Which products and versions are affected?
- Envoy Proxy Envoy >= 1.34.0, < 1.35.13; >= 1.36.0, < 1.36.9; >= 1.37.0, < 1.37.5; >= 1.38.0, < 1.38.3.
- Is there a fix for CVE-2026-48706?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-48706 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-48706?
- Check whether you run Envoy Proxy Envoy 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 write overflow exists in Envoy's TCP StatsD sink (TcpStatsdSink) due to improper buffer management during metric formatting. The flusher reserves a fixed 16KiB memory slice; however, if a single metric name exceeds this capacity, the rotation logic incorrectly allocates another fixed 16KiB slice instead of a larger one, leading to an out-of-bounds write via memcpy. An attacker can trigger this by sending HTTP or gRPC requests with extremely long paths (over 16KiB) if the 'grpc_stats' filter is configured with 'stats_for_all_methods: true'. This can result in a denial-of-service (DoS) or remote code execution (RCE). The issue is fixed in versions 1.35.13, 1.36.9, 1.37.5, and 1.38.3.
Affected products
- Envoy Proxy Envoy >= 1.34.0, < 1.35.13; >= 1.36.0, < 1.36.9; >= 1.37.0, < 1.37.5; >= 1.38.0, < 1.38.3
Timeline
- 2026-06-23: advisory: GitHub Security Advisory published
- 2026-06-26: disclosed: CVE published to NVD