U-Boot before 2026.10-rc3 with CONFIG_IP_DEFRAG enabled contains an out-of-bounds write vulnerability in the __net_defragment() function in net/net.c. (CVE-2026-71971)
U-Boot versions prior to 2026.10-rc3 with CONFIG_IP_DEFRAG enabled have an out-of-bounds write vulnerability in the __net_defragment() function. This flaw allows remote attackers to send crafted IP fragments during netboot, potentially corrupting adjacent memory and causing the bootloader to crash.
AI Analysis
Technical Summary
The vulnerability identified as CVE-2026-71971 affects U-Boot bootloader versions before 2026.10-rc3 when the CONFIG_IP_DEFRAG option is enabled. It is an out-of-bounds write in the __net_defragment() function located in net/net.c. Remote attackers can exploit this by sending a specially crafted IP fragment with a non-zero offset and the More-Fragments flag set during netboot. This can lead to memory corruption adjacent to the buffer and result in a crash of the bootloader.
Potential Impact
Exploitation of this vulnerability can cause denial of service by crashing the bootloader due to memory corruption. There is no indication from the data that confidentiality or availability beyond the crash is affected. The CVSS score of 8.2 reflects high severity due to remote network attack vector, no required privileges or user interaction, and the potential for significant availability impact.
Mitigation Recommendations
A fix is available in U-Boot version 2026.10-rc3 and later. Users should upgrade to version 2026.10-rc3 or newer to remediate this vulnerability. No additional mitigation guidance is provided or required beyond applying the official patch.
U-Boot before 2026.10-rc3 with CONFIG_IP_DEFRAG enabled contains an out-of-bounds write vulnerability in the __net_defragment() function in net/net.c. (CVE-2026-71971)
Description
U-Boot versions prior to 2026.10-rc3 with CONFIG_IP_DEFRAG enabled have an out-of-bounds write vulnerability in the __net_defragment() function. This flaw allows remote attackers to send crafted IP fragments during netboot, potentially corrupting adjacent memory and causing the bootloader to crash.
CVSS v3.1
Score 8.2high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability identified as CVE-2026-71971 affects U-Boot bootloader versions before 2026.10-rc3 when the CONFIG_IP_DEFRAG option is enabled. It is an out-of-bounds write in the __net_defragment() function located in net/net.c. Remote attackers can exploit this by sending a specially crafted IP fragment with a non-zero offset and the More-Fragments flag set during netboot. This can lead to memory corruption adjacent to the buffer and result in a crash of the bootloader.
Potential Impact
Exploitation of this vulnerability can cause denial of service by crashing the bootloader due to memory corruption. There is no indication from the data that confidentiality or availability beyond the crash is affected. The CVSS score of 8.2 reflects high severity due to remote network attack vector, no required privileges or user interaction, and the potential for significant availability impact.
Mitigation Recommendations
A fix is available in U-Boot version 2026.10-rc3 and later. Users should upgrade to version 2026.10-rc3 or newer to remediate this vulnerability. No additional mitigation guidance is provided or required beyond applying the official patch.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-9gg4-qrm6-f795
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-71971"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6abc5d48680226ef6899ba8b
Added to database: 09/30/2026, 00:52:24 UTC
Last enriched: 09/30/2026, 01:06:12 UTC
Last updated: 09/30/2026, 01:06:16 UTC
Views: 4
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