osrg GoBGP up to 4.3.0 pkg/packet/bgp/bgp.go DecodeFromBytes data[1] off-by-one

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.6$0-$5k2.76

Summaryinfo

A vulnerability marked as problematic has been reported in osrg GoBGP up to 4.3.0. Affected is the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. The manipulation of the argument data[1] leads to off-by-one. This vulnerability is referenced as CVE-2026-5123. Remote exploitation of the attack is possible. No exploit is available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability was found in osrg GoBGP up to 4.3.0 and classified as problematic. This issue affects the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. The manipulation of the argument data[1] with an unknown input leads to a off-by-one vulnerability. Using CWE to declare the problem leads to CWE-193. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value. Impacted is availability.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-5123. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit.

Applying the patch 67c059413470df64bc20801c46f64058e88f800f is able to eliminate this problem. The bugfix is ready for download at github.com.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.7
VulDB Meta Temp Score: 3.6

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Off-by-one
CWE: CWE-193 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 67c059413470df64bc20801c46f64058e88f800f

Timelineinfo

03/30/2026 Advisory disclosed
03/30/2026 +0 days VulDB entry created
03/30/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 3342
Status: Confirmed

CVE: CVE-2026-5123 (🔒)
GCVE (CVE): GCVE-0-2026-5123
GCVE (VulDB): GCVE-100-354155

Entryinfo

Created: 03/30/2026 09:55
Changes: 03/30/2026 09:55 (57)
Complete: 🔍
Submitter: Sunxj
Cache ID: 216:52B:103

Submitinfo

Accepted

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