Book page text, count, and author/title length is not limited in PocketMine-MP
The advisory, in context
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
Affected packages
Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.
Earlier releases before 3.26.5
Fixed in 3.26.5
150 explicitly affected versions
3.0.0, 3.0.1, 3.0.10, 3.0.11, 3.0.12, 3.0.2, 3.0.3, 3.0.4, 3.0.5, 3.0.6, 3.0.7, 3.0.8, 3.0.9, 3.1.0, 3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.1.5, 3.1.6, 3.1.7, 3.1.8, 3.10.0, 3.10.1, 3.11.0, 3.11.1, 3.11.2, 3.11.3, 3.11.4, 3.11.5, 3.11.6, 3.11.7, 3.12.0, 3.12.1, 3.12.2, 3.12.3, 3.12.4, 3.12.5, 3.12.6, 3.13.0, 3.13.1, 3.14.0, 3.14.1, 3.14.2, 3.14.3, 3.15.0, 3.15.1, 3.15.2, 3.15.3, 3.15.4, 3.16.0, 3.16.1, 3.17.0, 3.17.1, 3.17.2, 3.17.3, 3.17.4, 3.17.5, 3.17.6, 3.17.7, 3.18.0, 3.18.1, 3.18.2, 3.19.0, 3.19.1, 3.19.2, 3.19.3, 3.2.0, 3.2.1, 3.2.2, 3.2.3, 3.2.4, 3.2.5, 3.2.6, 3.2.7, 3.20.0, 3.21.0, 3.21.1, 3.22.0, 3.22.1, 3.22.2, 3.22.3, 3.22.4, 3.22.5, 3.23.0, 3.23.1, 3.24.0, 3.25.0, 3.25.1, 3.25.2, 3.25.3, 3.25.4, 3.25.5, 3.25.6, 3.26.0, 3.26.1, 3.26.2, 3.26.3, 3.26.4, 3.3.0, 3.3.1, 3.3.2, 3.3.3, 3.3.4, 3.4.0, 3.4.1, 3.4.2, 3.4.3, 3.5.0, 3.5.1, 3.5.10, 3.5.11, 3.5.12, 3.5.13, 3.5.2, 3.5.3, 3.5.4, 3.5.5, 3.5.6, 3.5.7, 3.5.8, 3.5.9, 3.6.0, 3.6.1, 3.6.2, 3.6.3, 3.6.4, 3.6.5, 3.6.6, 3.7.0, 3.7.1, 3.7.2, 3.7.3, 3.8.0, 3.8.1, 3.8.2, 3.8.3, 3.8.4, 3.8.5, 3.8.6, 3.8.7, 3.9.0, 3.9.1, 3.9.2, 3.9.3, 3.9.4, 3.9.5, 3.9.6, 3.9.7, 3.9.8
View affected-version evidence
{
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.26.5"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"3.0.0",
"3.0.1",
"3.0.10",
"3.0.11",
"3.0.12",
"3.0.2",
"3.0.3",
"3.0.4",
"3.0.5",
"3.0.6",
"3.0.7",
"3.0.8",
"3.0.9",
"3.1.0",
"3.1.1",
"3.1.2",
"3.1.3",
"3.1.4",
"3.1.5",
"3.1.6",
"3.1.7",
"3.1.8",
"3.10.0",
"3.10.1",
"3.11.0",
"3.11.1",
"3.11.2",
"3.11.3",
"3.11.4",
"3.11.5",
"3.11.6",
"3.11.7",
"3.12.0",
"3.12.1",
"3.12.2",
"3.12.3",
"3.12.4",
"3.12.5",
"3.12.6",
"3.13.0",
"3.13.1",
"3.14.0",
"3.14.1",
"3.14.2",
"3.14.3",
"3.15.0",
"3.15.1",
"3.15.2",
"3.15.3",
"3.15.4",
"3.16.0",
"3.16.1",
"3.17.0",
"3.17.1",
"3.17.2",
"3.17.3",
"3.17.4",
"3.17.5",
"3.17.6",
"3.17.7",
"3.18.0",
"3.18.1",
"3.18.2",
"3.19.0",
"3.19.1",
"3.19.2",
"3.19.3",
"3.2.0",
"3.2.1",
"3.2.2",
"3.2.3",
"3.2.4",
"3.2.5",
"3.2.6",
"3.2.7",
"3.20.0",
"3.21.0",
"3.21.1",
"3.22.0",
"3.22.1",
"3.22.2",
"3.22.3",
"3.22.4",
"3.22.5",
"3.23.0",
"3.23.1",
"3.24.0",
"3.25.0",
"3.25.1",
"3.25.2",
"3.25.3",
"3.25.4",
"3.25.5",
"3.25.6",
"3.26.0",
"3.26.1",
"3.26.2",
"3.26.3",
"3.26.4",
"3.3.0",
"3.3.1",
"3.3.2",
"3.3.3",
"3.3.4",
"3.4.0",
"3.4.1",
"3.4.2",
"3.4.3",
"3.5.0",
"3.5.1",
"3.5.10",
"3.5.11",
"3.5.12",
"3.5.13",
"3.5.2",
"3.5.3",
"3.5.4",
"3.5.5",
"3.5.6",
"3.5.7",
"3.5.8",
"3.5.9",
"3.6.0",
"3.6.1",
"3.6.2",
"3.6.3",
"3.6.4",
"3.6.5",
"3.6.6",
"3.7.0",
"3.7.1",
"3.7.2",
"3.7.3",
"3.8.0",
"3.8.1",
"3.8.2",
"3.8.3",
"3.8.4",
"3.8.5",
"3.8.6",
"3.8.7",
"3.9.0",
"3.9.1",
"3.9.2",
"3.9.3",
"3.9.4",
"3.9.5",
"3.9.6",
"3.9.7",
"3.9.8"
]
}From 4.0.0 before 4.0.5
Fixed in 4.0.5
5 explicitly affected versions
4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.0.4
View affected-version evidence
{
"ranges": [
{
"events": [
{
"introduced": "4.0.0"
},
{
"fixed": "4.0.5"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.0.0",
"4.0.1",
"4.0.2",
"4.0.3",
"4.0.4"
]
}