VulnerabilityPublished 15 Sep 2026Updated 17 Sep 2026

CVE-2026-91982: vikunja · Insufficiently Protected Credentials

Affects vikunjaSource CVE Database V5

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Not known to be exploited · CVSS 4.3 Medium : upgrade to 2.6.0 when convenient.

Data as of 30 Oct 2026, 20:25 UTC

CVSS 3.1 base score

4.3Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 28% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.6.0

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 15 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade vikunja and github.com/go-vikunja/vikunja to 2.6.0.

Affected software

Product	Affected	Fixed in
go-vikunjavikunja	Affected <2.6.0	Fixed in 2.6.0
Gogithub.com/go-vikunja/vikunja`pkg:golang/github.com/go-vikunja/vikunja`Other threats	Affected <2.6.0	Fixed in 2.6.0

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

The recommended fix is to stop returning the TOTP secret, provisioning URL, and QR code once TOTP is enabled, exposing them only during the enrollment phase. Alternatively, requiring password verification before returning these secrets would also mitigate the issue. If you cannot patch yet, restrict access tokens and sessions carefully to prevent unauthorized access.

Description

### 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.

Impact

The vulnerability allows an attacker who has obtained a victim's access token to extract the TOTP shared secret without additional authentication. This compromises the second factor authentication, enabling persistent account takeover by generating valid TOTP codes indefinitely. The attack leaves no logs or notifications, making detection difficult. The overall security assurance provided by TOTP is nullified in this scenario.

Summary

CVE-2026-91982 describes an insufficiently protected credential vulnerability in go-vikunja vikunja where the API endpoint GET /api/v1/user/settings/totp returns the full TOTP secret and provisioning URL without requiring the user's password or any step-up authentication once TOTP is enabled. This contrasts with the disabling flow which requires password verification. An attacker with the victim's access token can retrieve the secret and use it to generate valid TOTP codes, effectively defeating the second factor authentication. The secret should only be exposed during enrollment and not after TOTP is enabled.

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What to do

Affected software

Description

AI analysisMachine-generated, updated 9 Oct 2026, 22:48 UTC

Technical details

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