WebFig: authentication bypass

MikroTik RouterOS

MikroTik RouterOS through 7.24.5 contains a session token replay vulnerability in the WebFig interface that allows attackers to bypass authentication by replaying captured session tokens across new ECDH sessions.

Do this now

Check the MikroTik advisory for a fix, and restrict access to WebFig from untrusted networks until one is available.

Still cooking for RouterOS.

First seen: 27 Oct 2026
Last update: 27 Oct 2026, 14:18 UTC
Identifiers: CVE-2026-89035
CVSS: 7.4
Source: news
On the menu as: VPN & firewalls

Check this repository for exposure to one security incident from pwned.coffee. Report first, change nothing until I say so.

## WebFig: authentication bypass
Severity: high. Patch status: fix status unknown.
Affected: MikroTik RouterOS
Ids: CVE-2026-89035

MikroTik RouterOS through 7.24.5 contains a session token replay vulnerability in the WebFig interface that allows attackers to bypass authentication by replaying captured session tokens across new ECDH sessions.

## Steps
1. This touches infrastructure (vpn-edge). Look in terraform, ansible, cloud-init, Dockerfiles and docs for the product and version we run. If it isn't in the repo, say so and list what a human should check on the box.
2. RouterOS 7.24.x, <= 7.23.6: the CVE record names no fix; check the vendor advisory before assuming there is none. Until one ships: restrict network access to it.

## Fix by release line
| Line | State | Fix | Until then |
|---|---|---|---|
| RouterOS 7.24.x, <= 7.23.6 | not named in the CVE record | check the vendor advisory: https://www.vulncheck.com/advisories/mikrotik-routeros-webfig-session-token-replay-authentication-bypass | restrict network access to it |

## Report
A table: file, product or package, version in use, affected yes/no, exact fix. Then anything a human has to check outside the repo.

If you have the pwned.coffee MCP server (https://pwned.coffee/mcp), call lookup_cve("CVE-2026-89035") for the latest, and check_repo with this repo's lockfiles, Dockerfiles and workflows for a full receipt.
Sources: https://nvd.nist.gov/vuln/detail/CVE-2026-89035 https://www.vulncheck.com/advisories/mikrotik-routeros-webfig-session-token-replay-authentication-bypass
https://pwned.coffee/i/webfig-authentication-bypass-cve-2026-89035

Receipt

Exploitation: No known exploitation
Fix by release line: Product Affected Fixed in Source
RouterOS <= 7.24.5 fix not named in the CVE record: see vendor advisory CVE record (CNA) checked 27 Oct
RouterOS <= 7.23.6 fix not named in the CVE record: see vendor advisory CVE record (CNA) checked 27 Oct
The CVE record names no fix for 2 lines; the vendor’s advisory may: vulncheck.com
Score: CVSS 7.4 (high). CVSS 3.1 7.4 (CNA VulnCheck) for CVE-2026-89035
Last checked: 27 Oct 2026, 15:18 UTC

Product	Affected	Fixed in	Source
RouterOS	<= 7.24.5	fix not named in the CVE record: see vendor advisory	CVE record (CNA) checked 27 Oct
RouterOS	<= 7.23.6	fix not named in the CVE record: see vendor advisory	CVE record (CNA) checked 27 Oct

Sources: KEV – CVE record ✓ Vendor ✓

Sources

Wrong fix version, or a source we missed? Send it back to chef@pwned.coffee with the source, and we'll correct it here.

Totalone hot coffee