U-Boot 2026.04-rc3 Out-of-Bounds Read in tcp_rx_state_machine via tcp.c
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| u-boot | u-boot | up to 2026.04-rc3 | — | No fix listed | CNA |
- u-boot Vendoru-boot Affected up to 2026.04-rc3 Fixed in — No fix listed CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:denx:u-boot:*:*:*:*:*:*:*:* | before 2026.04 | Vulnerable | u-boot |
| cpe:2.3:a:denx:u-boot:2026.04:rc1:*:*:*:*:*:* | 2026.04 rc1 | Vulnerable | u-boot |
| cpe:2.3:a:denx:u-boot:2026.04:rc2:*:*:*:*:*:* | 2026.04 rc2 | Vulnerable | u-boot |
| cpe:2.3:a:denx:u-boot:2026.04:rc3:*:*:*:*:*:* | 2026.04 rc3 | Vulnerable | u-boot |
- cpe:2.3:a:denx:u-boot:*:*:*:*:*:*:*:* Versions before 2026.04 Vulnerable ·u-boot
- cpe:2.3:a:denx:u-boot:2026.04:rc1:*:*:*:*:*:* Versions 2026.04 rc1 Vulnerable ·u-boot
- cpe:2.3:a:denx:u-boot:2026.04:rc2:*:*:*:*:*:* Versions 2026.04 rc2 Vulnerable ·u-boot
- cpe:2.3:a:denx:u-boot:2026.04:rc3:*:*:*:*:*:* Versions 2026.04 rc3 Vulnerable ·u-boot
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2026-29007
- 2026-10-03 Alias added: GHSA-572m-4pr8-48pj
References
Advisory 1
Other 1
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- TI-2025-28794 A lack of signature verification in the bootloader of DENX Software Engineering Das… CVSS 3.1MEDIUM 6.5
- TI-2020-06770 In Das U-Boot through 2020.01, a double free has been found in the cmd/gpt.c… CVSS 3.1CRITICAL 9.8
- TI-2022-12898 nfs_lookup_reply in net/nfs.c in Das U-Boot through 2022.04 (and through 2022.07-rc2) has… CVSS 3.1CRITICAL 9.8
- TI-2019-10569 An issue was discovered in Das U-Boot through 2019.07. CVSS 3.0CRITICAL 9.8
- TI-2019-10568 An issue was discovered in Das U-Boot through 2019.07. CVSS 3.0CRITICAL 9.8
Sources
- CVE-2026-29007 · CVE Program
- CVE-2026-29007 · NVD
- FIRST EPSS
- GHSA-572m-4pr8-48pj · GitHub Advisory Database · CC BY 4.0
- CVE-2026-29007 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences