CVE-2020-37277
PocketMine-MP before 3.15.4 Denial of Service via InventoryTransaction
PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the InventoryTransaction component's findResultItem() method. Malicious clients can send specially crafted InventoryTransactionPackets with multiple conflicting pathways to cause exponential processing complexity, freezing the server.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
PocketMine-MP before 3.15.4 Denial of Service via InventoryTransaction
PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the InventoryTransaction component's findResultItem() method. Malicious clients can send specially crafted InventoryTransactionPackets with multiple conflicting pathways to cause exponential processing complexity, freezing the server.
- Record
CVE-2020-37277- CVSS 4.0
- 7.1 High
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 - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
EUVDEUVD-2020-31270
PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the InventoryTransaction component's findResultItem() method. Malicious clients can send specially crafted InventoryTransactionPackets with multiple conflicting pathways to cause exponential processing complexity, freezing the server.
- Record
EUVD-2020-31270- CVSS 4.0
- 7.1 High
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-w7p4-2gxc-qg89
PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the...
PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the InventoryTransaction component's findResultItem() method. Malicious clients can send specially crafted InventoryTransactionPackets with multiple conflicting pathways to cause exponential processing complexity, freezing the server.
- Record
GHSA-w7p4-2gxc-qg89- CVSS 4.0
- 7.1 High
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/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
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
GitHub AdvisoriesGHSA-8jq6-w5cg-wm45 No score
Exploitable inventory component chaining in PocketMine-MP
Impact
Specially crafted InventoryTransactionPackets sent by malicious clients were able to exploit the behaviour of InventoryTransaction->findResultItem() and cause it to take an abnormally long time to execute (causing an apparent server freeze).
The affected code is intended to compact conflicting InventoryActions which are in the same InventoryTransaction by flattening them into a single action. When multiple pathways to a result existed, the complexity of this flattening became exponential.
The problem was fixed by bailing when ambiguities are detected.
At the time of writing, this exploit is being used in the wild by attackers to deny service to servers.
Patches
Upgrade to 3.15.4 or newer.
Workarounds
No practical workarounds are possible, short of backporting the fix or implementing checks in a plugin listening to DataPacketReceiveEvent.
References
c368ebb5e74632bc622534b37cd1447b97281e20
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected]
- Record
GHSA-8jq6-w5cg-wm45- Weakness
- CWE-400
- Updated
- 2026-11-02
NVD
PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the InventoryTransaction component's findResultItem() method. Malicious clients can send specially crafted InventoryTransactionPackets with multiple conflicting pathways to cause exponential processing complexity, freezing the server.
- Record
CVE-2020-37277- CVSS 4.0
- 7.1 High
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/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
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
OSV
PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the InventoryTransaction component's findResultItem() method. Malicious clients can send specially crafted InventoryTransactionPackets with multiple conflicting pathways to cause exponential processing complexity, freezing the server.
- Record
CVE-2020-37277- CVSS 4.0
- 7.1 High
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/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
OSVGHSA-8jq6-w5cg-wm45 No score
Exploitable inventory component chaining in PocketMine-MP
Impact
Specially crafted InventoryTransactionPackets sent by malicious clients were able to exploit the behaviour of InventoryTransaction->findResultItem() and cause it to take an abnormally long time to execute (causing an apparent server freeze).
The affected code is intended to compact conflicting InventoryActions which are in the same InventoryTransaction by flattening them into a single action. When multiple pathways to a result existed, the complexity of this flattening became exponential.
The problem was fixed by bailing when ambiguities are detected.
At the time of writing, this exploit is being used in the wild by attackers to deny service to servers.
Patches
Upgrade to 3.15.4 or newer.
Workarounds
No practical workarounds are possible, short of backporting the fix or implementing checks in a plugin listening to DataPacketReceiveEvent.
References
c368ebb5e74632bc622534b37cd1447b97281e20
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected]
- Record
GHSA-8jq6-w5cg-wm45- Weakness
- CWE-400
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
pocketmine/pocketmine-mpPackagist |
before 3.15.4 | 3.15.4 |
pocketmine/pocketmine-mpPackagist |
before 3.15.4, plus listed versions 3.0.03.0.13.0.103.0.113.0.12 Show 45 moreShow less3.0.23.0.33.0.43.0.53.0.63.0.73.0.83.0.93.1.03.1.13.1.23.1.33.1.43.1.53.1.63.1.73.1.83.10.03.10.13.11.03.11.13.11.23.11.33.11.43.11.53.11.63.11.73.12.03.12.13.12.23.12.33.12.43.12.53.12.63.13.03.13.13.14.03.14.13.14.23.14.33.15.03.15.13.15.23.15.33.2.0 |
3.15.4 |
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-2020-37277 is a high vulnerability (CVSS 7.1) in Pmmp Pocketmine-mp, published November 11, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.53%, the 45th percentile. Fixed in pocketmine/pocketmine-mp 3.15.4.
References
github.com/pmmp/PocketMine-MP/security/advisories/GHSA-8jq6-w5cg-wm45
vulncheck.com/advisories/pocketmine-mp-before-3.15.4-denial-of-service-via-inventorytransaction
nvd.nist.gov/vuln/detail/CVE-2020-37277
Left out here: 58 versions. The JSON record has them.