# CVE-2026-19977: EFM ipTIME A3004T Session Validation httpcon_check_session_url improper authentication

> Remote attackers can bypass authentication in EFM ipTIME A3004T routers due to improper session validation, potentially gaining unauthorized access.

- **Severity:** Critical 10.0 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Aug 2026
- **Updated:** 18 Aug 2026
- **Also known as:** GHSA-6h4w-hx37-cqg3

## What is CVE-2026-19977?

CVE-2026-19977 is a critical authentication bypass vulnerability in EFM ipTIME A3004T, published on 17 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability was detected in EFM ipTIME A3004T 14.19.0. The affected element is the function httpcon_check_session_url of the component Session Validation. Performing a manipulation results in improper authentication. Remote exploitation of the attack is possible. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2026-19977?


## How do I fix CVE-2026-19977?

No fix has been published for CVE-2026-19977 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-19977 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-19977 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-19977 and fix it if it is affected.

What it is: CVE-2026-19977 is a critical authentication bypass vulnerability in EFM ipTIME A3004T, published on 17 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-19977 exists.

Affected product: EFM ipTIME A3004T. 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-2026-19977/ (Markdown: https://insights.sbomify.com/CVE-2026-19977/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-19977
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-19977
- OSV: https://osv.dev/vulnerability/CVE-2026-19977

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-19977/
Summaries are generated and may contain mistakes; the official description above is the record.