Vikunja before 2.6.0 TOTP Secret Disclosure via API

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Vikunja before 2.6.0 continues to expose the raw TOTP shared secret after enrollment through the GET /api/v1/user/settings/totp and /api/v1/user/settings/totp/qrcode endpoints without re-authentication. Attackers with a valid access token can read the secret, import it into their own authenticator, and generate valid codes indefinitely to defeat the second factor and enable account takeover.

Source published

15 Sep 2026 15:18:26 UTC

Source modified

17 Sep 2026 15:14:33 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 4.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

CVSS 4.0 · 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Vikunja before 2.6.0 continues to expose the raw TOTP shared secret after enrollment through the GET /api/v1/user/settings/totp and /api/v1/user/settings/totp/qrcode endpoints without re-authentication. Attackers with a valid access token can read the secret, import it into their own authenticator, and generate valid codes indefinitely to defeat the second factor and enable account takeover.

Source published

Sep 15, 2026, 3:18:26 PM (timezone not stated)

Source modified

Sep 17, 2026, 3:14:33 PM (timezone not stated)

Observed here

7 Nov 2026 15:25:09 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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EUVD CVSS 4.0 · 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Vikunja before 2.6.0 continues to expose the raw TOTP shared secret after enrollment through the GET /api/v1/user/settings/totp and /api/v1/user/settings/totp/qrcode endpoints without re-authentication. Attackers with a valid access token can read the secret, import it into their own authenticator, and generate valid codes indefinitely to defeat the second factor and enable account takeover.

Source published

15 Sep 2026 16:17:55 UTC

Source modified

17 Sep 2026 16:18:32 UTC

Observed here

25 Oct 2026 16:19:22 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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CVSS 4.0 · [email protected] · Secondary · 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/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 3.1 · [email protected] · Secondary · 4.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

### Summary Once a user has TOTP enabled, the API still hands back the raw shared secret to anyone holding that account's access token. Reading it doesn't ask for the password, even though disabling TOTP does. So a stolen token, an XSS, or a browser left open is enough to copy the second factor into your own authenticator and keep generating valid codes indefinitely. ### Details `GET /api/v1/user/settings/totp` returns the full TOTP object, including the secret field and the otpauth:// provisioning URL. `GET /api/v1/user/settings/totp/qrcode` renders the same secret as a QR image. Neither requires re-authentication, the access token alone is enough. This is inconsistent with the rest of the flow: `POST /api/v1/user/settings/totp/disable` calls CheckUserPassword before it will turn TOTP off. So the destructive action is gated behind the password, but reading out the secret that backs the second factor isn't. There's also no reason for the secret to be readable at all once enrollment is finished, the client only needs it during setup. The fix is to stop returning secret/url/the QR code once enabled is true (only expose them during the enrollment window). Requiring the password on the read, like disable already does, would also be reasonable. ### PoC The attacker needs the victim's access token, from an XSS, a leaked/stolen token, or an unlocked session. TOTP must already be enabled on the account. 1. With the victim's bearer token, call: ``` GET /api/v1/user/settings/totp Authorization: Bearer <victim_token> ``` The response contains the shared secret and the otpauth:// URL: ``` {"secret": "<base32 secret>", "enabled": true, "url": "otpauth://totp/..."} ``` 2. Paste that secret (or scan `/api/v1/user/settings/totp/qrcode`) into any authenticator app. 3. It now produces the same 6-digit codes as the victim's device. Nothing is logged and the victim gets no notification. ### Impact This defeats the purpose of the second factor. 2FA is supposed to survive exactly this situation, a compromised password or a hijacked session, but a single read of the account's own settings hands over the shared secret with no step-up check and no trace. Combined with a known or later-recovered password, it's a durable account takeover that TOTP was meant to prevent.

Source published

9 Oct 2026 20:51:17 UTC

Source modified

19 Oct 2026 21:41:10 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Publisher rating · MODERATE

### Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-88f6-4rjv-x774. This link is maintained to preserve external references. ### Original Description Vikunja before 2.6.0 continues to expose the raw TOTP shared secret after enrollment through the GET /api/v1/user/settings/totp and /api/v1/user/settings/totp/qrcode endpoints without re-authentication. Attackers with a valid access token can read the secret, import it into their own authenticator, and generate valid codes indefinitely to defeat the second factor and enable account takeover.

Source published

15 Sep 2026 18:32:30 UTC

Source modified

9 Oct 2026 21:00:06 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/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

Publisher rating · MODERATE

Vikunja: TOTP secret is readable after enrollment, no step-up auth in code.vikunja.io/api. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. (If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.) The additional affected modules and versions are: code.vikunja.io/api before v2.6.0.

Source published

19 Oct 2026 21:08:26 UTC

Source modified

19 Oct 2026 21:31:52 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.