CVE-2019-15612

Pending-session persistence via incomplete password-reset invalidation

Published Feb 4, 2020 · Updated Aug 5, 2024

Session fixation in affected Nextcloud Server releases allows attackers to retain pending 2FA logins after a password reset. The password-change path does not revoke a session token for a login paused at the second-factor challenge, so the pending authentication state survives the credential change. Exploitation requires access to an already pending 2FA session; public materials do not disclose how that state produces the reported data-read or data-write impact.

CVSS severity5.9
Medium
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Session fixation in affected Nextcloud Server releases allows attackers to retain pending 2FA logins after a password reset. The password-change path does not revoke a session token for a login paused at the second-factor challenge, so the pending authentication state survives the credential change. Exploitation requires access to an already pending 2FA session; public materials do not disclose how that state produces the reported data-read or data-write impact.

The record

CVE
CVE-2019-15612
Published
Feb 4, 2020
Updated
Aug 5, 2024
Vendor
Nextcloud GmbH
Product
Nextcloud Server
Classifications
CWE-384, T1078
Attack vector
physical
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 4, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=15.0.3

What conditions does exploitation require?

Attack vectorphysical
Required privilegesauthenticated

What is affected?

Nextcloud GmbH · Nextcloud Serverversion=15.0.3

Published CVSS scores

3.2NIST NVDAV:L/AC:L/Au:S/C:P/I:P/A:N
5.9NIST NVDCVSS:3.1/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorphysical
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-384Session Fixation
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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