# CVE-2020-10739: Null dereference in istio/envoy

> Attackers can cause a denial of service in Istio by sending crafted packets when Telemetry v2 is enabled, affecting ingress gateways and sidecars.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Jun 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-wr89-rp47-qc87, RHSA-2020:2148

## What is CVE-2020-10739?

CVE-2020-10739 is a high-severity vulnerability in istio.io istio/envoy, published on 2 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Istio 1.4.x before 1.4.9 and Istio 1.5.x before 1.5.4 contain the following vulnerability when telemetry v2 is enabled: by sending a specially crafted packet, an attacker could trigger a Null Pointer Exception resulting in a Denial of Service. This could be sent to the ingress gateway or a sidecar, triggering a null pointer exception which results in a denial of service. This also affects servicemesh-proxy where a null pointer exception flaw was found in servicemesh-proxy. When running Telemetry v2 (not on by default in version 1.4.x), an attacker could send a specially crafted packet to the ingress gateway or proxy sidecar, triggering a denial of service.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2020-10739?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `servicemesh-proxy` | Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.2-2.el8 |

Products: Istio Istio.

## How do I fix CVE-2020-10739?

Upgrade to a fixed version.

## Is CVE-2020-10739 being exploited?

There is no known exploitation of CVE-2020-10739 in the wild and no public exploit code.

## Other vulnerabilities in istio.io istio/envoy

- [CVE-2021-31921](https://insights.sbomify.com/CVE-2021-31921/): Missing authorization in n/a (critical 9.8)
- [CVE-2021-34824](https://insights.sbomify.com/CVE-2021-34824/): Information disclosure in n/a (high 8.8)
- [CVE-2026-31837](https://insights.sbomify.com/CVE-2026-31837/): Istio JWKS resolver to prevent private key material from being exposed when JWKS fetch fails. (high 8.7)
- [CVE-2021-39155](https://insights.sbomify.com/CVE-2021-39155/): Authorization Policy Bypass Due to Case Insensitive Host Comparison (high 8.3)
- [CVE-2021-39156](https://insights.sbomify.com/CVE-2021-39156/): Fragments in Path May Lead to Authorization Policy Bypass (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-10739 and fix it if it is affected.

What it is: CVE-2020-10739 is a high-severity vulnerability in istio.io istio/envoy, published on 2 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-10739 in the wild and no public exploit code.

Affected product: istio.io istio/envoy. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2020-10739/ (Markdown: https://insights.sbomify.com/CVE-2020-10739/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-10739
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-10739
- OSV: https://osv.dev/vulnerability/CVE-2020-10739

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-10739/
Summaries are generated and may contain mistakes; the official description above is the record.