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CVE-2026-63201

netopeer2-server logging has format string vulnerability via subtree filter

CVSS score

7.1

EPSS probability

—

Risk score

0.7

Published

2 h ago

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

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Vulnerability description

DayBreach AI Explanation

Verified against sources

netopeer2-server Format String Vulnerability

Sources read

2

Source agreement

Tam uyum

Evidence confidence

%61

Short explanation

A format string vulnerability in netopeer2-server allows low-privileged authenticated users to trigger a remote denial of service.

Why does it matter?

This flaw allows low-privileged attackers to crash the netopeer2-server service, disrupting critical network configuration management operations.

What should be done?

  • Follow vendor advisory guidance
  • Review published updates
Note on uncertainty

The sources give limited detail on some technical conditions. Review the chain of evidence below before deciding how to act.

Chain of evidence and sources3 verified claims

netopeer2-server, kimlik doğrulamış düşük ayrıcalıklı bir kullanıcının geçersiz subtree filter içeren get RPC göndermesiyle uzaktan çökertilebilir.

Sorun, src/log.c içindeki np2log() işlevinin zaten biçimlendirilmiş bir arabelleği biçim dizesi olarak ele almasından kaynaklanmaktadır.

Sürüm 2.8.7 üzerinde AddressSanitizer ile yapılan testlerde servis dışı bırakılma doğrulanmış, güvenilir uzaktan kod çalıştırma teyit edilmemiştir.

Show the technical text from the sources

Netopeer2 is a server for implementing network configuration management based on the `NETCONF` Protocol. In affected versions, a low-privileged authenticated `NETCONF` user can remotely crash `netopeer2-server` by sending a `get RPC` with an invalid `subtree filter` whose text contains format specifiers. In `src/netconf.c`, `np2srv_rpc_get_cb()` sends the invalid value through `ERR()` to `np2log_printf()`, where `vsnprintf()` first formats the message safely. In `src/log.c`, that already formatted buffer is subsequently passed to `np2log()` as the format string itself, causing `vsyslog()` to interpret attacker-controlled percent sequences and read invalid pointer arguments. The reported denial of service was confirmed on version 2.8.7 using `NETCONF`-over-SSH and AddressSanitizer; reliable remote code execution was not confirmed. `The advisory identifies 2.8.8 as patched`; repository comparisons verify the fix in public release 2.8.21. The affected/fixed boundary remains unresolved because no public 2.8.8 tag was located, which does not establish the status of an untagged 2.8.8 build.

CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CWE: CWE-134

This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-63201 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1CESNETnetopeer2 View
Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
7.1CVSS V4_0HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE CNA
7.1CVSS V40HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/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:XNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63201 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-63201 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsLow
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

7.1 / 10
Attack VectorNetworkComplexityLowPrivilegesLowUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow privileges
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

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Weakness Type (CWE & CAPEC)

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CVE-2026-63201 · netopeer2-server logging has format string…