CVE-2026-5123
osrg GoBGP bgp.go DecodeFromBytes off-by-one
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
osrg GoBGP bgp.go DecodeFromBytes off-by-one
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
- Record
CVE-2026-5123- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X - CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C - CVSS 3.0
- 3.7 Low
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C - CVSS 2.0
- 2.6
AV:N/AC:H/Au:N/C:N/I:N/A:P/E:ND/RL:OF/RC:C - Weakness
- CWE-193, CWE-189
- Updated
- 2026-11-02
EUVDEUVD-2026-17109
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
- Record
EUVD-2026-17109- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-m763-9mqf-95rq
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function...
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
- Record
GHSA-m763-9mqf-95rq- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
NVD
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
- Record
CVE-2026-5123- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 2.0
- 2.6 Low
AV:N/AC:H/Au:N/C:N/I:N/A:P - Weakness
- CWE-189, CWE-193
- Updated
- 2026-11-02
OSV
osrg GoBGP bgp.go DecodeFromBytes off-by-one
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
- Record
CVE-2026-5123- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X - Weakness
- CWE-189, CWE-193
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-5123
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
- Record
DEBIAN-CVE-2026-5123- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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 - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-5123
A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.
- Record
UBUNTU-CVE-2026-5123- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
gobgpDebian:12 |
All versions, plus listed versions 3.10.0-13.16.0-13.19.0-13.21.0-13.23.0-1 Show 22 moreShow less3.25.0-13.27.0-13.28.0-13.29.0-13.30.0-13.31.0-13.32.0-13.33.0-13.35.0-13.36.0-13.36.0-24.3.0-14.4.0-14.5.0-14.5.0-1~bpo13+14.6.0-14.6.0-24.6.0-2~bpo13+14.7.0-14.7.0-1~bpo13+14.8.0-14.8.0-2~exp1 |
None known |
gobgpDebian:13 |
All versions, plus listed versions 3.36.0-24.3.0-14.4.0-14.5.0-14.5.0-1~bpo13+1 Show 7 moreShow less4.6.0-14.6.0-24.6.0-2~bpo13+14.7.0-14.7.0-1~bpo13+14.8.0-14.8.0-2~exp1 |
None known |
gobgpDebian:14 |
before 4.4.0-1, plus listed versions 3.36.0-24.3.0-1 |
4.4.0-1 |
gobgpUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 1.15-11.29-11.29-1ubuntu0.1+esm11.29-1ubuntu0.1+esm2 |
None known |
gobgpUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1.33-12.11.0-12.12.0-12.12.0-1ubuntu0.1~esm12.12.0-1ubuntu0.1~esm22.12.0-1ubuntu0.1~esm3 |
None known |
gobgpUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 2.25.0-22.25.0-32.25.0-3build12.25.0-3ubuntu0.12.25.0-3ubuntu0.1+esm12.25.0-3ubuntu0.1+esm22.25.0-3ubuntu0.1+esm32.25.0-3ubuntu0.1+esm4 |
None known |
gobgpUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 3.16.0-1build13.19.0-13.21.0-13.23.0-13.23.0-1ubuntu0.1 Show 7 moreShow less3.23.0-1ubuntu0.23.23.0-1ubuntu0.2+esm13.23.0-1ubuntu0.33.23.0-1ubuntu0.3+esm13.23.0-1ubuntu0.3+esm23.23.0-1ubuntu0.3+esm33.23.0-1ubuntu0.3+esm4 |
None known |
gobgpUbuntu:25.10 |
All versions, plus listed versions 3.35.0-13.36.0-2 |
None known |
gobgpUbuntu:26.10 |
All versions, plus listed versions 3.36.0-2build14.8.0-1 |
None known |
gobgpUbuntu:Pro:26.04:LTS |
All versions, plus listed versions 3.36.0-23.36.0-2build13.36.0-2ubuntu0.1~esm1 |
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-2026-5123 is a medium vulnerability (CVSS 6.3) in Osrg Gobgp, published March 30, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 36th percentile. Fixed in gobgp 4.4.0-1.