CVE-2019-3977

highpriority · track · 30OT risk · elevatedEPSS 0.011 · 64 %ileEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.06% (64th) EPSS

CVSS 8.5 · high

Is it mine?

5 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-26

RouterOS 6.45.6 Stable, RouterOS 6.44.5 Long-term, and below insufficiently validate where upgrade packages are download from when using the autoupgrade feature. Therefore, a remote attacker can trick the router into "upgrading" to an older version of RouterOS and possibly reseting all the system's usernames and passwords.

cvss

Technical severity, 0–10. One row per scoring source.

8.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–8.5

v2.08.5highAV:N/AC:L/Au:N/C:N/I:C/A:Pprimary · NVD / NIST USexploitability 10 · impact 7.8

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · FSTEC (BDU) RU

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-494USprimaryCWE-494US

affected products (5)

Products and version ranges known to be affected.

n/a MikroTik RouterOS≤ RouterOS 6.45.6 Stable and below. RouterOS 6.44.5 Long-term and below.enisa_euvdEU
MikroTik RouterOS≤ 6.44.5 Long-termfstec_bduRU
MikroTik RouterOS≤ 6.45.6 Stablefstec_bduRU
mikrotik routeros≤ 6.44.5nvdUScpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*
mikrotik routeros≤ 6.45.6nvdUScpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2019-10-29modified 2026-06-17

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+306 more

references (5)

External citations — patches, advisories, analysis.

scry

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