Bug 2553134 (CVE-2026-18660)

Summary: CVE-2026-18660 org.eclipse.jetty/jetty-server: org.eclipse.jetty/jetty-proxy: Eclipse Jetty: Access control bypass via case-sensitive host filtering
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: abrianik, anthomas, asyoung, ataylor, ccranfor, csuconic, dbruscin, dfreiber, dhanak, drosa, drow, dsimansk, ehelms, ewittman, fmariani, ggainey, ggrzybek, gmalinko, gtully, janstey, jburrell, jhollowa, jpasqual, jpechane, jraez, jsherman, juwatts, jwon, kaycoth, kingland, kvanderr, mcarlett, mdellweg, mhulan, mnovotny, nipatil, nmoumoul, osousa, pantinor, parichar, pcreech, pdelbell, pjindal, prichard, rchan, rgemmell, rgodfrey, rhel-process-autobot, rkubis, rstepani, sausingh, sdawley, smallamp, sthirugn, tasato, tbish, tcunning, tlavocat, tmalecek, vkumar, watson-tool-maintainers, yfang
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Eclipse Jetty. This vulnerability allows a remote attacker to bypass access controls and reach restricted resources. The issue occurs because the server and proxy components perform case-sensitive validation on host allowlists and denylists. By sending requests with altered character casing in the host name, an attacker can circumvent configured host filtering policies.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2553957, 2553958, 2553959, 2553960, 2553961, 2553962, 2553963, 2553964    
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Description OSIDB Bzimport 2026-10-15 09:41:31 UTC 
In Eclipse Jetty, across various versions of `jetty-server`, and `jetty-proxy`, the host whitelist/blacklist is case-sensitive, and would allow hosts through that only differ by case.