Eclipse Jetty - EE8: Improper Handling of Alternate Encoding
CVE-2026-10050 is a critical-severity improper handling of alternate encoding vulnerability in Eclipse Jetty - EE8 from Eclipse Foundation, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Eclipse Jetty - EE8 versions: 12.0.0 through 12.0.35; 12.1.0 through 12.1.9. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.63% chance of exploitation within 30 days, higher than 51% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Jetty to 9.4.63 or 10.0.31 or 11.0.31 or 12.0.36, whichever matches your release line, or a later version.
- Read the advisory on github.com 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.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Eclipse Foundation | Eclipse Jetty - EE8 | 12.0.0 through 12.0.35; 12.1.0 through 12.1.9 | Not stated |
| Eclipse Foundation | Eclipse Jetty - EE9 | 12.0.0 through 12.0.35; 12.1.0 through 12.1.9 | Not stated |
| Eclipse Foundation | Eclipse Jetty | 9.4.0 through 9.4.62; 10.0.0 through 10.0.30; 11.0.0 through 11.0.30; 12.0.0 through 12.0.35; 12.1.0 through 12.1.9 | Not stated |
| Eclipse | Jetty | 9.4.0 up to, but not including, 9.4.63; 10.0.0 up to, but not including, 10.0.31; 11.0.0 up to, but not including, 11.0.31; 12.0.0 up to, but not including, 12.0.36; 12.1.0 up to, but not including, 12.1.10 | 9.4.63, 10.0.31, 11.0.31, 12.0.36, 12.1.10 |
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
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (eclipse.org) |
| CVSS 3.1 | 9.1 | Critical | NVD |
Official description
In Eclipse Jetty, the Digest authentication server-side component uses ISO-8859-1 to encode the password as bytes. This was done because the initial specification for HTTP did not specify explicitly a charset, and it was assumed to be ISO-8859-1 for historical reasons. If the password contains characters that cannot be represented in ISO-8859-1, they are silently replaced by `?`. This happens with passwords that contain Chinese, Cyrillic or Greek characters, for example: `αβ123` converts to `??123`. An attacker can send a request with a digest `Authorization` header crafted with a password made of only `?` characters; the server would match any password of the same length that contains non-ISO-8859-1 characters. Recent HTTP Digest [RFC-7616](https://datatracker.ietf.org/doc/html/rfc7616) supports a `charset` parameters that defaults to UTF-8 that allows for correct encoding/decoding of passwords.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Handling of Alternate Encoding
The product does not properly handle when an input uses an alternate encoding that is valid for the control sphere to which the input is being sent.
How developers prevent this class of flaw
- Avoid making decisions based on names of resources (e.g. files) if those resources can have alternate names.
- Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
More Improper Handling of Alternate Encoding vulnerabilities (CWE-173)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
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