CVE-2026-84700
Pika Unauthenticated Replication Access via Internal Protobuf Port
PikiwiDB (Pika) v3.5.7 exposes an internal protobuf replication server on a port derived from the client port plus 2000 (e.g. 11221 when the default client port 9221 is used) that does not authenticate incoming requests. Although requirepass is intended to gate replication — a slave presents it as masterauth inside its MetaSync request — only the MetaSync handler (HandleMetaSyncRequest) validates it; the frame dispatcher (DealMessage) does not require a completed or attempted MetaSync before routing other message types to their handlers. As a result, an unauthenticated remote attacker can connect directly to the replication port and issue TrySync, DBSync, BinlogSync, and RemoveSlaveNode requests, obtaining the full-sync snapshot and live write stream and removing replica nodes, even when requirepass is configured.
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
- High
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used 8.8
Pika Unauthenticated Replication Access via Internal Protobuf Port
PikiwiDB (Pika) v3.5.7 exposes an internal protobuf replication server on a port derived from the client port plus 2000 (e.g. 11221 when the default client port 9221 is used) that does not authenticate incoming requests. Although requirepass is intended to gate replication — a slave presents it as masterauth inside its MetaSync request — only the MetaSync handler (HandleMetaSyncRequest) validates it; the frame dispatcher (DealMessage) does not require a completed or attempted MetaSync before routing other message types to their handlers. As a result, an unauthenticated remote attacker can connect directly to the replication port and issue TrySync, DBSync, BinlogSync, and RemoveSlaveNode requests, obtaining the full-sync snapshot and live write stream and removing replica nodes, even when requirepass is configured.
- Record
CVE-2026-84700- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N - CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L - Weakness
- CWE-306
- Updated
- 2026-11-02
EUVDEUVD-2026-69791 8.8
PikiwiDB (Pika) v3.5.7 exposes an internal protobuf replication server on a port derived from the client port plus 2000 (e.g. 11221 when the default client port 9221 is used) that does not authenticate incoming requests. Although requirepass is intended to gate replication — a slave presents it as masterauth inside its MetaSync request — only the MetaSync handler (HandleMetaSyncRequest) validates it; the frame dispatcher (DealMessage) does not require a completed or attempted MetaSync before routing other message types to their handlers. As a result, an unauthenticated remote attacker can connect directly to the replication port and issue TrySync, DBSync, BinlogSync, and RemoveSlaveNode requests, obtaining the full-sync snapshot and live write stream and removing replica nodes, even when requirepass is configured.
- Record
EUVD-2026-69791- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-747h-6gh8-p8v2 8.8
PikiwiDB (Pika) v3.5.7 exposes an internal protobuf replication server on a port derived from the...
PikiwiDB (Pika) v3.5.7 exposes an internal protobuf replication server on a port derived from the client port plus 2000 (e.g. 11221 when the default client port 9221 is used) that does not authenticate incoming requests. Although requirepass is intended to gate replication — a slave presents it as masterauth inside its MetaSync request — only the MetaSync handler (HandleMetaSyncRequest) validates it; the frame dispatcher (DealMessage) does not require a completed or attempted MetaSync before routing other message types to their handlers. As a result, an unauthenticated remote attacker can connect directly to the replication port and issue TrySync, DBSync, BinlogSync, and RemoveSlaveNode requests, obtaining the full-sync snapshot and live write stream and removing replica nodes, even when requirepass is configured.
- Record
GHSA-747h-6gh8-p8v2- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/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
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L - Weakness
- CWE-306
- Updated
- 2026-11-02
NVD 8.8
PikiwiDB (Pika) v3.5.7 exposes an internal protobuf replication server on a port derived from the client port plus 2000 (e.g. 11221 when the default client port 9221 is used) that does not authenticate incoming requests. Although requirepass is intended to gate replication — a slave presents it as masterauth inside its MetaSync request — only the MetaSync handler (HandleMetaSyncRequest) validates it; the frame dispatcher (DealMessage) does not require a completed or attempted MetaSync before routing other message types to their handlers. As a result, an unauthenticated remote attacker can connect directly to the replication port and issue TrySync, DBSync, BinlogSync, and RemoveSlaveNode requests, obtaining the full-sync snapshot and live write stream and removing replica nodes, even when requirepass is configured.
- Record
CVE-2026-84700- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/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
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L - Weakness
- CWE-306
- Updated
- 2026-11-02
OSV 8.8
Pika Unauthenticated Replication Access via Internal Protobuf Port
PikiwiDB (Pika) v3.5.7 exposes an internal protobuf replication server on a port derived from the client port plus 2000 (e.g. 11221 when the default client port 9221 is used) that does not authenticate incoming requests. Although requirepass is intended to gate replication — a slave presents it as masterauth inside its MetaSync request — only the MetaSync handler (HandleMetaSyncRequest) validates it; the frame dispatcher (DealMessage) does not require a completed or attempted MetaSync before routing other message types to their handlers. As a result, an unauthenticated remote attacker can connect directly to the replication port and issue TrySync, DBSync, BinlogSync, and RemoveSlaveNode requests, obtaining the full-sync snapshot and live write stream and removing replica nodes, even when requirepass is configured.
- Record
CVE-2026-84700- CVSS 4.0
- 8.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-306
- Updated
- 2026-11-02
Affected products
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-2026-84700 is a high vulnerability (CVSS 8.8) in Openatomfoundation Pikiwidb, published September 2, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.58%, the 48th percentile. No source names a fixed version.
References
github.com/OpenAtomFoundation/pikiwidb
github.com/OpenAtomFoundation/pikiwidb/issues/3270
github.com/OpenAtomFoundation/pikiwidb/blob/v3.5.7/src/pika_repl_server_conn.cc
vulncheck.com/advisories/pika-unauthenticated-replication-access-via-internal-protobuf-port
nvd.nist.gov/vuln/detail/CVE-2026-84700
github.com/advisories/GHSA-747h-6gh8-p8v2
github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84700.json