Apache APISIX: Cross-Site Request Forgery
CVE-2026-49871 is a critical-severity cross-site request forgery vulnerability in Apache APISIX from Apache, with a CVSS 3.1 base score of 9.3 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected Apache APISIX versions: 3.0.0 through 3.16.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.35% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Apisix to 3.17.0 or a later version.
- Read the advisory on lists.apache.org for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Apache | Apache APISIX | 3.0.0 through 3.16.0 | Not stated |
| Apache | Apisix | 3.0.0 up to, but not including, 3.17.0 | 3.17.0 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 2.1 | Low | CNA (apache.org) |
| CVSS 3.1 | 9.3 | Critical | NVD |
Official description
Cross-Site Request Forgery (CSRF) vulnerability in the cas-auth plugin under default configurations. This defect allows a remote attacker that manages to send a victim to a webpage controlled by them can cause the victim's browser to become authenticated as a different identity. Actions the victim takes upstream are then attributed to attackers identity. This issue affects Apache APISIX: from 3.0.0 through 3.16.0. Users are recommended to upgrade to version 3.17.0, which fixes the issue.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Cross-Site Request Forgery
The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
How developers prevent this class of flaw
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, use anti-CSRF packages such as the OWASP CSRFGuard. Another example is the ESAPI Session Management control, which includes a component for CSRF.
- Ensure that the application is free of cross-site scripting issues (CWE-79), because most CSRF defenses can be bypassed using attacker-controlled script.
- Generate a unique nonce for each form, place the nonce into the form, and verify the nonce upon receipt of the form. Be sure that the nonce is not predictable (CWE-330).
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- openwall.com/lists/oss-security/2026/06/19/14Third Party Advisory
Other vulnerabilities in Apache APISIX
- 7.0 High severity
- 7.8 High severity
- 8.2 High severity
- 8.1 High severity
- 7.5 High severity
- 7.5 High severity
Recent Cross-Site Request Forgery vulnerabilities
- 8.6 High severity
- 8.1 High severity
- 9.6 Critical severity
- 8.8 High severity
- 8.0 High severity
- 8.0 High severity
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