CVE-2026-29009
U-Boot < 2026.07-rc2 Buffer Overflow in nfs_readlink_reply() via NFS READLINK
U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.8
U-Boot < 2026.07-rc2 Buffer Overflow in nfs_readlink_reply() via NFS READLINK
U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
- Record
CVE-2026-29009- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-120
- Updated
- 2026-11-02
EUVDEUVD-2026-42333
8.8
U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
- Record
EUVD-2026-42333- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-rqrq-75p3-gc68
8.8
U-Boot through 2026.04-rc3 contains a buffer overflow vulnerability in nfs_readlink_reply() (net...
U-Boot through 2026.04-rc3 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
- Record
GHSA-rqrq-75p3-gc68- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-120
- Updated
- 2026-11-02
NVD
8.8
U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
- Record
CVE-2026-29009- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-120
- Updated
- 2026-11-02
OSV
8.8
U-Boot < 2026.07-rc2 Buffer Overflow in nfs_readlink_reply() via NFS READLINK
U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
- Record
CVE-2026-29009- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-120
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-29009
9.8
U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
- Record
DEBIAN-CVE-2026-29009- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVOESA-2026-2994
8.2
uboot-tools security update
This package includes the mkimage program, which allows generation of U-Boot images in various formats, and the fw_printenv and fw_setenv programs to read and modify U-Boot's environment.
Security Fix(es):
U-Boot through 2026.04-rc3 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.(CVE-2026-29009)
- Record
OESA-2026-2994- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-29009
8.8
U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.
- Record
UBUNTU-CVE-2026-29009- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
u-bootDebian:12 |
All versions, plus listed versions 2023.01+dfsg-22023.01+dfsg-2+deb12u12023.01+dfsg-2+deb12u22023.01+dfsg-2+deb12u32023.04+dfsg-1 Show 20 moreShow less2023.04~rc2+dfsg-12023.04~rc5+dfsg-12023.07+dfsg-12023.07~rc4+dfsg-12023.07~rc5+dfsg-12024.01+dfsg-12024.01+dfsg-22024.01+dfsg-32024.01+dfsg-42024.01+dfsg-52024.01+dfsg-62024.01+dfsg-72024.01~rc6+dfsg-12024.01~rc6+dfsg-22025.01-12025.01-22025.01-32025.01-3.12025.01-3.22026.10~rc5-1 |
None known |
u-bootDebian:13 |
All versions, plus listed versions 2025.01-32025.01-3+deb13u12025.01-3.12025.01-3.22026.10~rc5-1 |
None known |
u-bootDebian:14 |
All versions, plus listed versions 2025.01-32025.01-3.12025.01-3.22026.10~rc5-1 |
None known |
uboot-toolsopenEuler:24.03-LTS-SP3 |
before 2024.01-5.oe2403sp3 | 2024.01-5.oe2403sp3 |
uboot-toolsopenEuler:24.03-LTS-SP4 |
before 2024.01-5.oe2403sp4 | 2024.01-5.oe2403sp4 |
uboot-toolsopenEuler:20.03-LTS-SP4 |
before 2020.07-12.oe2003sp4 | 2020.07-12.oe2003sp4 |
uboot-toolsopenEuler:22.03-LTS-SP4 |
before 2021.10-13.oe2203sp4 | 2021.10-13.oe2203sp4 |
uboot-toolsopenEuler:24.03-LTS-SP1 |
before 2024.01-5.oe2403sp1 | 2024.01-5.oe2403sp1 |
u-bootUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 2015.04+dfsg1-2ubuntu12015.10+dfsg1-22015.10+dfsg1-32015.10+dfsg1-42016.01+dfsg1-1 Show 7 moreShow less2016.01+dfsg1-1ubuntu12016.01+dfsg1-2ubuntu12016.01+dfsg1-2ubuntu22016.01+dfsg1-2ubuntu32016.01+dfsg1-2ubuntu52016.01+dfsg1-2ubuntu5+esm12016.01+dfsg1-2ubuntu5+esm2 |
None known |
u-bootUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 2016.03+dfsg1-6ubuntu22018.07~rc3+dfsg1-0ubuntu1~18.04.12018.07~rc3+dfsg1-0ubuntu2~18.04.12018.07~rc3+dfsg1-0ubuntu3~18.04.12019.07+dfsg-1ubuntu4~18.04.1 Show 4 moreShow less2020.10+dfsg-1ubuntu0~18.04.22020.10+dfsg-1ubuntu0~18.04.32020.10+dfsg-1ubuntu0~18.04.3+esm12020.10+dfsg-1ubuntu0~18.04.3+esm2 |
None known |
Show 8 moreShow less
| Package | Affected | Fixed |
|---|---|---|
u-bootUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 2019.07+dfsg-1ubuntu32019.07+dfsg-1ubuntu52019.07+dfsg-1ubuntu62020.10+dfsg-1ubuntu0~20.04.22021.01+dfsg-3ubuntu0~20.04.1 Show 6 moreShow less2021.01+dfsg-3ubuntu0~20.04.32021.01+dfsg-3ubuntu0~20.04.42021.01+dfsg-3ubuntu0~20.04.52021.01+dfsg-3ubuntu0~20.04.62021.01+dfsg-3ubuntu0~20.04.6+esm12021.01+dfsg-3ubuntu0~20.04.6+esm2 |
None known |
u-bootUbuntu:22.04:LTS |
All versions, plus listed versions 2021.07+dfsg-0ubuntu82021.07+dfsg-0ubuntu92021.07+dfsg-0ubuntu102022.01+dfsg-2ubuntu12022.01+dfsg-2ubuntu2 Show 8 moreShow less2022.01+dfsg-2ubuntu2.12022.01+dfsg-2ubuntu2.32022.01+dfsg-2ubuntu2.42022.01+dfsg-2ubuntu2.52022.01+dfsg-2ubuntu2.62022.01+dfsg-2ubuntu2.72022.01+dfsg-2ubuntu2.82022.01+dfsg-2ubuntu2.9 |
None known |
u-boot-nezhaUbuntu:22.04:LTS |
All versions, plus listed versions 2021.09+git20211008.62392d3-0ubuntu12022.04+git20220405.7446a472-0ubuntu0.12022.04+git20220405.7446a472-0ubuntu0.22022.04+git20220405.7446a472-0ubuntu0.32022.04+git20220405.7446a472-0ubuntu0.4 |
None known |
u-bootUbuntu:24.04:LTS |
All versions, plus listed versions 2023.07+dfsg-1ubuntu22024.01+dfsg-1ubuntu12024.01+dfsg-1ubuntu22024.01+dfsg-1ubuntu32024.01+dfsg-1ubuntu4 Show 9 moreShow less2024.01+dfsg-1ubuntu52024.01+dfsg-1ubuntu5.12024.01+dfsg-1ubuntu5.22025.01-0ubuntu0.24.04.12025.01-0ubuntu0.24.04.22025.10-0ubuntu0.24.04.12025.10-0ubuntu0.24.04.22025.10-0ubuntu0.24.04.32025.10-0ubuntu0.24.04.4 |
None known |
u-boot-nezhaUbuntu:24.04:LTS |
All versions, plus listed versions 2022.10-1089-g528ae9bc6c-0ubuntu22024.01~rc1-190-g2e89b706f5-0ubuntu12024.01~rc1-190-g2e89b706f5-0ubuntu22024.01~rc1-190-g2e89b706f5-0ubuntu2.24.04.2 |
None known |
u-bootUbuntu:25.10 |
All versions, plus listed versions 2025.01-1~0ubuntu22025.01-3ubuntu12025.01-3ubuntu22025.01-3ubuntu42025.10-0ubuntu0.25.10.1 |
None known |
u-bootUbuntu:26.10 |
All versions, plus listed versions 2025.10-0ubuntu22025.10-0ubuntu32025.10-0ubuntu42025.10-0ubuntu52025.10-0ubuntu6 |
None known |
u-bootUbuntu:26.04:LTS |
All versions, plus listed versions 2025.01-3ubuntu42025.10-0ubuntu12025.10-0ubuntu22025.10-0ubuntu2.12025.10-0ubuntu2.2 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-29009 is a high vulnerability (CVSS 8.8) in Denx U-boot, published July 8, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.74%, the 54th percentile. Fixed in uboot-tools 2024.01-5.oe2403sp3.
References
y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns
lists.denx.de/pipermail/u-boot/2026-May/617853.html
git.u-boot-project.org/u-boot/u-boot/-/releases/v2026.07-rc2
git.u-boot-project.org/u-boot/u-boot/-/commit/d6694018eaddefac6aae974f9cec72fd6e58f1bc
u-boot.org
vulncheck.com/advisories/u-boot-rc3-buffer-overflow-in-nfs-readlink-reply-via-nfs-readlink
Show 8 moreShow less
nvd.nist.gov/vuln/detail/CVE-2026-29009
github.com/advisories/GHSA-rqrq-75p3-gc68
github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29009.json
github.com/u-boot/u-boot
security-tracker.debian.org/tracker/CVE-2026-29009
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2026-2994
ubuntu.com/security/CVE-2026-29009
cve.org/CVERecord?id=CVE-2026-29009