Intel

CVE-2026-93345

MikroTik RouterOS: Schwachstelle ermöglicht Denial of Service

mediumEPSS 0.5%

Description

MikroTik RouterOS before 7.25beta4 contains an improper input validation vulnerability in the labelled-VPN NLRI iterators of the routing service that allows an unauthenticated on-path attacker to crash the BGP service by sending a malformed MP_REACH_NLRI UPDATE message with a prefix-length value below the minimum valid for a labelled-VPN NLRI, which passes validation while describing a route with a negative-length address portion. Attackers can repeatedly send a single BGP UPDATE packet carrying a VPNv4 or VPNv6 NLRI with an out-of-bounds prefix-length to indefinitely hold down the BGP plane, causing session termination without a NOTIFICATION and triggering a service malfunction on the device. The fix is carried only in 7.25beta4, a development build; the current stable release 7.24.2 and the current long-term release 7.23.5 both remain affected.

Source: BSI

Metrics

XIEM Effective CVSS
8.7
Source: cna-v4
EPSS percentile
40.1 %
High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status
—
Show all metrics
Severity
medium
Priority score
86.36
Exploit maturity
no public PoC known
CVSS v3
7.5
CVSS v4
8.7
EPSS score
0.5 %
Low — model estimates < 1% exploitation likelihood.
Published
2026-09-23 11:29 UTC
CWE
CWE-1284

Weakness classes (CWE)

  • CWE-1284Base

    Improper Validation of Specified Quantity in Input

    The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties.

    cwe.mitre.org →

References & sources

Reanalysis & status changes

Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

  1. CVE Modified2026-09-25 14:17 UTC· disclosure@vulncheck.com
    • Affected: Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/93xxx/CVE-2026-93345.json">CVE-2026-93345</a>
  2. CVE Modified2026-09-24 21:18 UTC· disclosure@vulncheck.com
    • Description: MikroTik RouterOS before 7.25beta4 contains an improper input validation vulnerability in the labelled-VPN NLRI iterators of the routing service that allows an unauthenticated on-path attacker to crash the BGP service by sending a malformed MP_REACH_NLRI UPDATE message with a prefix-length value below the minimum valid for a labelled-VPN NLRI, which passes validation while describing a route with a negative-length address portion. Attackers can repeatedly send a single BGP UPDATE packet carrying a VPNv4 or VPNv6 NLRI with an out-of-bounds prefix-length to indefinitely hold down the BGP plane, causing session termination without a NOTIFICATION and triggering a service malfunction on the device. → MikroTik RouterOS before 7.25beta4 contains an improper input validation vulnerability in the labelled-VPN NLRI iterators of the routing service that allows an unauthenticated on-path attacker to crash the BGP service by sending a malformed MP_REACH_NLRI UPDATE message with a prefix-length value below the minimum valid for a labelled-VPN NLRI, which passes validation while describing a route with a negative-length address portion. Attackers can repeatedly send a single BGP UPDATE packet carrying a VPNv4 or VPNv6 NLRI with an out-of-bounds prefix-length to indefinitely hold down the BGP plane, causing session termination without a NOTIFICATION and triggering a service malfunction on the device. The fix is carried only in 7.25beta4, a development build; the current stable release 7.24.2 and the current long-term release 7.23.5 both remain affected.
    • Affected: Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/93xxx/CVE-2026-93345.json">CVE-2026-93345</a>
  3. CVE Modified2026-09-22 19:16 UTC· 134c704f-9b21-4f2e-91b3-4a467353bcc0
    • SSVC: {"id":"CVE-2026-93345","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"yes"},{"technical…
  4. New CVE Received2026-09-22 18:17 UTC· disclosure@vulncheck.com
    • Description: MikroTik RouterOS before 7.25beta4 contains an improper input validation vulnerability in the labelled-VPN NLRI iterators of the routing service that allows an unauthenticated on-path attacker to crash the BGP service by sending a malformed MP_REACH_NLRI UPDATE message with a prefix-length value below the minimum valid for a labelled-VPN NLRI, which passes validation while describing a route with a negative-length address portion. Attackers can repeatedly send a single BGP UPDATE packet carrying a VPNv4 or VPNv6 NLRI with an out-of-bounds prefix-length to indefinitely hold down the BGP plane, causing session termination without a NOTIFICATION and triggering a service malfunction on the device.
    • CVSS V4.0: AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    • CVSS V3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    • CWE: CWE-1284

Linked CVEs