# CVE-2023-26046: teler-waf subject to bypass of common web attack threat rule with HTML entities payload

> Attackers can bypass WAF rules using HTML entities to execute arbitrary JavaScript, stealing credentials or hijacking sessions in applications using teler-waf.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Mar 2023
- **Updated:** 5 Mar 2025
- **Also known as:** GHSA-9f95-hhg4-pg4f, GO-2023-1597

## What is CVE-2023-26046?

CVE-2023-26046 is a medium-severity cross-site scripting vulnerability in kitabisa teler-waf, published on 2 Mar 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

teler-waf is a Go HTTP middleware that provides teler IDS functionality to protect against web-based attacks. In teler-waf prior to version 0.1.1 is vulnerable to bypassing common web attack rules when a specific HTML entities payload is used. This vulnerability allows an attacker to execute arbitrary JavaScript code on the victim's browser and compromise the security of the web application. The vulnerability exists due to teler-waf failure to properly sanitize and filter HTML entities in user input. An attacker can exploit this vulnerability to bypass common web attack threat rules in teler-waf and launch cross-site scripting (XSS) attacks. The attacker can execute arbitrary JavaScript code on the victim's browser and steal sensitive information, such as login credentials and session tokens, or take control of the victim's browser and perform malicious actions. This issue has been fixed in version 0.1.1.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-80 (Improper Neutralization of Script-Related HTML Tags in a Web Page)

## Which versions are affected by CVE-2023-26046?

3 open source packages ship an affected version, including github.com/kitabisa/teler-waf. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/kitabisa/teler-waf` | Go | All versions | 0.1.1 |
| `github.com/kitabisa/teler-waf` | Go | All versions | 0.1.1 |
| `github.com/kitabisa/teler-waf` | Go | All versions | 0.1.1 |

Products: Kitabisa Teler-Waf.

## How do I fix CVE-2023-26046?

Upgrade github.com/kitabisa/teler-waf to 0.1.1 or later.

## Is CVE-2023-26046 being exploited?

There is no known exploitation of CVE-2023-26046 in the wild and no public exploit code.

## Other vulnerabilities in kitabisa teler-waf

- [CVE-2023-26047](https://insights.sbomify.com/CVE-2023-26047/): teler-waf contains detection rule bypass via entities payload (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-26046 and fix it if it is affected.

What it is: CVE-2023-26046 is a medium-severity cross-site scripting vulnerability in kitabisa teler-waf, published on 2 Mar 2023. 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-2023-26046 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/kitabisa/teler-waf (Go): affected all versions; fixed in 0.1.1
- github.com/kitabisa/teler-waf (Go): affected all versions; fixed in 0.1.1
- github.com/kitabisa/teler-waf (Go): affected all versions; fixed in 0.1.1

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-2023-26046/ (Markdown: https://insights.sbomify.com/CVE-2023-26046/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-26046
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-26046
- OSV: https://osv.dev/vulnerability/CVE-2023-26046

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-26046/
Summaries are generated and may contain mistakes; the official description above is the record.