Bug 2506633

Summary: CVE-2026-29007 uboot-tools: U-Boot: Out-of-bounds read leads to denial of service via crafted TCP packets [fedora-all]
Product: [Fedora] Fedora Reporter: Thibault Guittet <tguittet>
Component: uboot-toolsAssignee: Peter Robinson <pbrobinson>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: dan, dennis, jean, jordan, mkorpershoek, nrevo, pbrobinson, pwhalen
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["791aa0d5-944d-42e8-a3f2-a30dd9e7cda4"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-07-23 22:18:38 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2498145    

Description Thibault Guittet 2026-07-23 21:50:40 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

U-Boot through 2026.04-rc3 contains an out-of-bounds read vulnerability in tcp_rx_state_machine() (net/tcp.c) when CONFIG_PROT_TCP is enabled, allowing remote attackers to read beyond TCP segment boundaries by crafting a malicious packet with a mismatched IP total length and TCP data offset field. Attackers can send a packet with an IP total length of 40 bytes and a TCP data offset claiming 60 bytes of header to cause tcp_parse_options() to read 40 bytes past the end of the TCP segment, potentially corrupting connection state variables such as rmt_win_scale and rmt_timestamp to disrupt TCP window calculations.

Comment 1 Peter Robinson 2026-07-23 22:18:38 UTC
Fedora enables the LWIP which is a different IP stack to this.