VulnerabilityPublished 27 May 2026Updated 17 Oct 2026

CVE-2026-44681: Python authlib · Prior to 1.6.12 and 1.7.1, an unauthenticated open redirect in Authlib's OpenIDImplicitGrant and OpenIDHybridGrant authorization endpoint lets a

Affects python-authlibSource GCVE Database

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Not known to be exploited · CVSS 6.1 Medium · fixed in 2.14.0_4 : update python-authlib when convenient.

Data as of 30 Oct 2026, 06:59 UTC

CVSS 3.1 base score

6.1Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 16% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.14.0_4, 1.41.0_1

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Changed
Confidentiality: Low
Integrity: Low
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: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
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: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on 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 27 May 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 29 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 mcpm to 2.14.0_4; kimi-cli to 1.41.0_1.

Affected software

Product	Affected	Fixed in
Ubuntu Pro 22.04 LTSpython-authlib`pkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps/jammy`Other threats	Affected 0.15.4-1 – 0.15.5-1ubuntu0.1~esm2 4 affected builds	Fixed in–
Ubuntu Pro 24.04 LTSpython-authlib`pkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps/noble`Other threats	Affected 1.2.1-1 – 1.3.0-1ubuntu0.1~esm2 4 affected builds	Fixed in–
Ubuntu 25.10python-authlib`pkg:deb/ubuntu/python-authlib?arch=source&distro=questing`Other threats	Affected =1.5.1-1 =1.5.2-1 =1.6.0-1	Fixed in–
Ubuntu Pro 26.04 LTSpython-authlib`pkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps/resolute`Other threats	Affected 1.6.0-1 – 1.6.7-1ubuntu0.1~esm1 5 affected builds	Fixed in–
Homebrewmcpm`pkg:brew/mcpm`Other threats	Affected >=2.1.0 <2.14.0_4	Fixed in 2.14.0_4
Homebrewkimi-cli`pkg:brew/kimi-cli`Other threats	Affected >=0.40 <1.41.0_1	Fixed in 1.41.0_1

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

AI-suggested

A fix is available in Authlib versions 1.6.12 and 1.7.1 and later. Users should upgrade to these or newer versions to remediate the vulnerability. No additional mitigation is required if the software is updated accordingly.

Description

Authlib versions prior to 1.6.12 and 1.7.1 contain an unauthenticated open redirect vulnerability in the OpenIDImplicitGrant and OpenIDHybridGrant authorization endpoints. This flaw is triggered by omitting the 'openid' scope in authorization requests, causing the server to redirect to an attacker-chosen URL without validating the redirect URI. The vulnerability affects servers supporting OpenID Connect Implicit or Hybrid flows and can be exploited without authentication or valid client IDs. While it does not directly leak tokens or authorization codes, it enables phishing attacks by leveraging the trusted authorization server's domain in the browser's URL bar. A fix is available for this vulnerability.

Impact

An attacker can exploit this vulnerability to perform phishing attacks by redirecting users to malicious sites while displaying the legitimate authorization server's domain in the URL bar. This could deceive users into divulging sensitive information. However, the vulnerability does not allow direct leakage of tokens or authorization codes. The flaw requires no authentication or valid client ID to exploit, increasing its risk.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 18 Oct 2026, 06:10 UTC

Technical details

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