Bug 2515988 (CVE-2026-72815)

Summary: CVE-2026-72815 github.com/go-chi/chi/middleware: go-chi chi: IP spoofing via X-Forwarded-For header allows bypass of access controls
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: aazores, abuckta, akhatavk, akoudelk, anthomas, aos-team-art-private, aprice, aruklets, asdas, cmah, crizzo, dfreiber, dhanak, dkuc, doconnor, dpaolell, drosa, drow, dsimansk, eaguilar, ebaron, eborisov, ehelms, eshamard, gbenhaim, ggainey, gparvin, gtanzill, jbalunas, jburrell, jbuscemi, jcantril, jdelft, jdobes, jmatsuok, jmitchel, jpasqual, jsamir, jsherril, jtolenti, jupierce, juwatts, jvasik, kaycoth, kgaikwad, kingland, kshier, lball, lbragsta, lgarciaa, mbiarnes, mdellweg, mhulan, mnovotny, mstipich, mwringe, ngough, niyer, nmoumoul, oezr, orabin, osousa, pcreech, pjindal, ppalepu, ppostler, prdhamdh, rblanco, rchan, rexwhite, rhaigner, rhel-process-autobot, rjohnson, rochandr, rojacob, sausingh, sdawley, sghai, sidsharm, smallamp, stcannon, sthirugn, suppawar, teagle, tmalecek, tsze, twaugh, veshanka, vkumar, vlaad, watson-tool-maintainers, wenshen, yguenane
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the `go-chi chi` RealIP middleware. This vulnerability allows a remote attacker to spoof their IP address by manipulating the `X-Forwarded-For` HTTP header. By exploiting this, an attacker can bypass IP-based access control lists and rate-limiting mechanisms, and forge log entries, potentially leading to unauthorized access or misattribution of actions.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2518038, 2518039, 2518040, 2518041, 2518042, 2518043, 2518044, 2518048, 2518049, 2518051, 2518052, 2518053, 2518055, 2518056, 2518037, 2518045, 2518046, 2518047, 2518050, 2518054, 2518057    
Bug Blocks:    

Description OSIDB Bzimport 2026-08-14 11:58:14 UTC 
go-chi chi versions >= 5.2.1 and before 5.3.0 contain an IP spoofing vulnerability in the RealIP middleware, which blindly trusts the first (leftmost) value of the X-Forwarded-For HTTP header. A remote attacker can bypass IP-based access control lists and rate-limiting mechanisms, and forge log entries, by supplying a spoofed IP address in the X-Forwarded-For header. The issue is fixed in version 5.3.0.