PT-2026-86780 · Pmmp+2 · Pocketmine-Mp+1
CVE-2022-51018
·
Published
2022-01-06
·
Updated
2026-09-07
CVSS v3.1
CVSS v4.0
7.1
High
| Vector | AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
Impact
Players can fill book pages with as many characters as they like; the server does not check this.
In addition, the maximum of 50 pages is also not enforced, meaning that players can create "book bombs".
This causes a variety of problems:
- Oversized NBT on the wire costing excess bandwidth for server and client
- Server crashes when saving region-based worlds due to exceeding maximum chunk size of 1 MB (PM3-specific)
- Server crashes if any book page exceeds 32 KiB (due to TAG String size limit) (PM4-specific)
This does, however, require that an attacker obtain a writable book in the first place in order to exploit the problem.
Patches
The bug has been fixed in 3.26.5 and 4.0.5.
Workarounds
Ban writable books, or use a plugin to cancel
PlayerEditBookEvent to cancel the event if strlen(text) > 1024 || mb strlen(text) > 256.For more information
If you have any questions or comments about this advisory:
- Email us at team@pmmp.io
Exploit
Fix
Resource Exhaustion
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Weakness Enumeration
Related Identifiers
Affected Products
Pocketmine-Mp
Pocketmine/Pocketmine-Mp