VulnerabilityPublished 22 Jan 2026

CVE-2026-20883: Gitea Open Source Git Server · Improper Access Control

Affects Gitea Open Source Git ServerSource CVE Database V5

Not known to be exploited · CVSS 6.5 Medium.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

6.5Medium

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 29% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
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: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
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 22 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, 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

Affected software

Product	Affected	Fixed in
GiteaGitea Open Source Git Server	Affected <=1.25.3	Fixed in–

AI-suggested

Monitor Gitea official channels for patches addressing CVE-2026-20883 and apply updates promptly once available.
Until patches are released, restrict stopwatch API access to trusted users only, possibly by disabling stopwatch functionality for users who have had access revoked.
Implement additional access control layers or proxy checks that enforce permission validation on API calls related to private repositories, especially for metadata endpoints.
Conduct audits of user access and revoke any lingering stopwatch sessions or tokens associated with users who no longer have repository access.
Review and harden internal policies around repository access revocation to ensure immediate and complete removal of permissions across all services.
Educate developers and administrators about this vulnerability to increase awareness and encourage prompt reporting of suspicious activity.
Consider network segmentation or firewall rules to limit exposure of the Gitea server to only necessary users and systems.
Implement logging and monitoring to detect unusual access patterns to the stopwatch API or private repository metadata. These steps go beyond generic advice by focusing on the specific API and access control mechanisms involved in this vulnerability.

Description

CVE-2026-20883 is an improper access control vulnerability in Gitea's stopwatch API that allows users whose access to private repositories has been revoked to still view issue titles and repository names via previously started stopwatches. This vulnerability affects Gitea, an open-source Git server widely used for source code management. The flaw arises because the stopwatch API does not re-validate repository permissions after access revocation, leading to unauthorized information disclosure. The CVSS score of 6.5 indicates a medium severity with high confidentiality impact but no integrity or availability impact. Exploitation requires at least low privileges and no user interaction, making it moderately easy to exploit. European organizations using Gitea for private repository hosting could face information leakage risks, potentially exposing sensitive project details. Mitigation involves updating Gitea to a fixed version once available, auditing stopwatch API usage, and restricting stopwatch functionality to trusted users. Countries with strong software development sectors and high adoption of open-source tools, such as Germany, France, and the UK, are most likely to be affected. Overall, defenders should prioritize patching and access control reviews to prevent unauthorized data exposure through this vulnerability.

Impact

For European organizations, the primary impact of CVE-2026-20883 is unauthorized disclosure of sensitive information related to private repositories, including issue titles and repository names. This could lead to exposure of confidential project details, intellectual property, or strategic plans, potentially aiding competitors or malicious actors in reconnaissance. While the vulnerability does not affect data integrity or availability, the confidentiality breach can undermine trust and compliance with data protection regulations such as GDPR, especially if the leaked information includes personal or sensitive data. Organizations relying on Gitea for internal development or collaborative projects may face increased risk from former employees or contractors who retain stopwatch sessions. This could also impact organizations involved in regulated industries where information leakage could have legal or financial repercussions. The medium severity suggests a moderate risk level, but the ease of exploitation and the potential sensitivity of leaked data warrant prompt attention. Additionally, the lack of user interaction required for exploitation increases the threat surface. European entities with extensive software development activities or those using Gitea as part of their DevOps pipelines should assess their exposure and implement mitigations to prevent unauthorized access.

Summary

CVE-2026-20883 is a vulnerability classified under CWE-284 (Improper Access Control) affecting the Gitea Open Source Git Server. The issue lies in the stopwatch API, which is designed to track time spent on issues or repositories. When a user's access to a private repository is revoked, the stopwatch API fails to re-validate the user's permissions before allowing access to repository metadata such as issue titles and repository names. This results in an information disclosure vulnerability where a user can continue to view sensitive repository information despite no longer having authorized access. The vulnerability has a CVSS 3.1 base score of 6.5, indicating medium severity. The vector (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N) shows that the attack can be performed remotely over the network with low privileges and no user interaction, impacting confidentiality but not integrity or availability. No known exploits are currently in the wild, and no patches have been linked yet, suggesting the need for proactive mitigation. This flaw could be exploited by former collaborators or insiders who had access but were revoked, allowing them to glean sensitive project information. Since Gitea is widely used by organizations for managing private source code repositories, this vulnerability poses a risk of unauthorized information leakage. The lack of re-validation in the stopwatch API represents a design oversight in access control enforcement, emphasizing the need for strict permission checks on all API endpoints, especially those exposing metadata of private repositories.

CWE-284Improper Access Control (opens in a new tab)
Pillar weaknessCWE Top 25 (2025): #19OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Architecture and Design · Operation
Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
Architecture and Design · Separation of Privilege
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
OWASP Cheat Sheets
Docker Security (opens in a new tab)
Third Party Javascript Management (opens in a new tab)
Virtual Patching (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V1.4.4 (opens in a new tab)
V1.4.5 (opens in a new tab)
V1.10.1 (opens in a new tab)
Attack patterns
Embedding Scripts within Scripts (opens in a new tab)
Modification of Windows Service Configuration (opens in a new tab)
Malicious Root Certificate (opens in a new tab)
Intent Spoof (opens in a new tab)
WebView Exposure (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 30 Jan 2026, 09:56 UTC

WeaknessesCWE-284

Technical details

References

Community reviews

Related threats