Bug 2488081 (CVE-2026-44249)

Summary: CVE-2026-44249 netty-handler: netty-handler: IPv6 subnet rule bypass due to incorrect masking operation
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: aazores, abrianik, anthomas, ant, aschwart, asoldano, aszczucz, ataylor, avibelli, bbaranow, bbrownin, bgeorges, bmaxwell, boliveir, bstansbe, ccranfor, cescoffi, chfoley, cmah, dandread, dbruscin, dhanak, dkreling, dlofthou, drichtar, drosa, dsimansk, eaguilar, ebaron, ehelms, ewittman, fmariani, fmongiar, ggainey, ggrzybek, gmalinko, gsmet, istudens, ivassile, iweiss, janstey, jkoehler, jmartisk, jnethert, jolong, jpechane, jraez, juwatts, jwon, kaycoth, kgaikwad, kingland, kvanderr, kverlaen, lphiri, lthon, manderse, mcarlett, mhulan, mnovotny, mosmerov, mposolda, mstipich, msvehla, nipatil, nmoumoul, nwallace, olubyans, osousa, pantinor, parichar, pcreech, pdelbell, pesilva, pgallagh, pjindal, pmackay, probinso, rchan, rexwhite, rgodfrey, rguimara, rkubis, rmartinc, rruss, rstancel, rstepani, rsvoboda, sausingh, sbiarozk, sdawley, smallamp, ssilvert, sthirugn, sthorger, swoodman, tasato, tcunning, thjenkin, tmalecek, tqvarnst, vdosoudi, vmuzikar, yfang
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in netty-handler, a component of the Netty network application framework. A remote attacker can exploit an incorrect masking operation in the IpSubnetFilterRule.compareTo() function to bypass configured IPv6 subnet rules. This allows valid public IP addresses to circumvent intended network restrictions, potentially leading to unauthorized access or exposure of services.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-11 22:02:27 UTC
Netty is a network application framework for development of protocol servers and clients. In netty-handler prior to versions 4.1.135.Final and 4.2.15.Final, an attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo(). Valid public IP addresses can bypass the restrictions. Versions 4.1.135.Final and 4.2.15.Final patch the issue.