# CVE-2026-73431: Reusable Account Activation and Recovery Tokens Allow Repeated Account Takeover in vulnerability-lookup

> Attackers can repeatedly take over accounts by replaying captured activation or recovery tokens because the application fails to invalidate them after use.

- **Severity:** High 8.8 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Aug 2026
- **Updated:** 12 Aug 2026
- **Also known as:** GHSA-w4vj-gm7w-293h

## What is CVE-2026-73431?

CVE-2026-73431 is a high-severity vulnerability in vulnerability-lookup, published on 12 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Vulnerability-Lookup contains an 
authentication weakness in its account activation and password-recovery 
mechanism. Activation and recovery links were generated using stateless 
signed tokens containing only the user's login. Although the token 
signature and age were validated, the application did not track whether a
 token had already been successfully used. As a result, a captured 
activation or password-recovery link remained valid for the entire 
configured TOKEN_VALIDITY_PERIOD, even after the associated password had been changed. 

An attacker who obtains a valid 
activation or recovery token could therefore replay it multiple times 
during its validity period to set a new password and repeatedly take 
control of the affected account. In addition, tokens were not bound to a
 specific purpose, allowing the same token mechanism to be used across 
activation and recovery workflows. The patch introduces purpose-bound 
tokens and a random nonce whose SHA-256 digest is stored with the user 
account. The nonce is invalidated after a successful password change, 
making tokens single-use, while issuing a new token invalidates any 
previously issued token.  The password-setting operation now explicitly consumes the token before committing the account change. 

Successful exploitation requires 
the attacker to obtain a currently valid activation or recovery link, 
but does not require knowledge of the victim's existing password or an 
authenticated session.

Weakness: CWE-294 (Authentication Bypass by Capture-replay)

## Which versions are affected by CVE-2026-73431?


## How do I fix CVE-2026-73431?

No fix has been published for CVE-2026-73431 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-73431 being exploited?

There is no known exploitation of CVE-2026-73431 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73431 and fix it if it is affected.

What it is: CVE-2026-73431 is a high-severity vulnerability in vulnerability-lookup, published on 12 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-73431 in the wild and no public exploit code.

Affected product: vulnerability-lookup. 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-2026-73431/ (Markdown: https://insights.sbomify.com/CVE-2026-73431/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73431
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73431
- OSV: https://osv.dev/vulnerability/CVE-2026-73431

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73431/
Summaries are generated and may contain mistakes; the official description above is the record.