CVE Intelligence
High

CVE-2026-7736 — osrg GoBGP mrt.go parseRibEntry integer underflow

A vulnerability was determined in osrg GoBGP up to 4.3.0. Affected by this vulnerability is the function parseRibEntry of the file pkg/packet/mrt/mrt.go. Executing a manipulation can lead to integer underflow. It is possible to launch the attack remotely. Upgrading to version 4.4.0 addresses this issue. This patch is called 76d911046344a3923cbe573364197aa081944592. It is suggested to upgrade the affected component.

Published May 4, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: VulDB

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.6% (30-day exploitation probability)+7
  • Technical severity (high)+6
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.63%
ahead of 49% of scored CVEs · Oct 14, 2026
Affects
Osrg
Gobgp
CVSS base
7.5
High · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — github.com (NIST National Vulnerability Database)
  • Documented patch — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Osrg Gobgp).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Osrg Gobgp < 4.4.0 Vulnerable NIST National Vulnerability Database
Osrg Gobgp version 4.0version 4.1version 4.2version 4.3.0 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
6.9 CVSS 4.0 Medium — — cna@vuldb.com via NIST National Vulnerability Database
6.9 CVSS 4.0 Medium — — VulDB via CVE Program (cve.org) e CISA ADP
7.5 CVSS 3.1 High 3.9 3.6 nvd@nist.gov via NIST National Vulnerability Database
7.3 CVSS 3.1 High 3.9 3.4 cna@vuldb.com via NIST National Vulnerability Database
7.3 CVSS 3.1 High — — VulDB via CVE Program (cve.org) e CISA ADP
7.3 CVSS 3.0 High — — VulDB via CVE Program (cve.org) e CISA ADP
7.5 CVSS 2.0 High 10.0 6.4 cna@vuldb.com via NIST National Vulnerability Database
7.5 CVSS 2.0 High — — VulDB via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 7.5 (NVD (NIST)) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-189

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.63%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · osrg/gobgp
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 7.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    May 4, 2026 · VulDB

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

Elsewhere on this site

Osrg
every CVE for this vendor
CWE-189
other pages naming this weakness

Related CVEs (same products)

  • High CVE-2026-42285 GoBGP: Panic in AdjRib.Update via malformed BGP Update message (Nil Pointer Dereference) May 7, 2026
  • High CVE-2026-41642 GoBGP: Remote Denial of Service (Panic) via Malformed Well-known Path Attribute May 7, 2026
  • High CVE-2026-41643 GoBGP: Remote Denial of Service (Panic) in UpdatePathAttrs4ByteAs via Malformed BGP UPDATE May 7, 2026
  • High CVE-2026-37461 Out-of-bounds Read in Osrg Gobgp May 4, 2026
  • High CVE-2026-7737 osrg GoBGP BMP Parser bmp.go BMPStatisticsReport.ParseBody out-of-bounds May 4, 2026
  • High CVE-2026-7734 osrg GoBGP SRv6 L3 Service prefix_sid.go SRv6L3ServiceAttribute.DecodeFromBytes denial of service May 4, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-7736 is "osrg GoBGP mrt.go parseRibEntry integer underflow", rated High. It affects Gobgp (Osrg); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.63% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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