Description
A weakness has been identified in BYVoid OpenCC up to 1.1.9. This vulnerability affects the function opencc::MaxMatchSegmentation of the file src/MaxMatchSegmentation.cpp. This manipulation causes heap-based buffer overflow. The attack is restricted to local execution. The exploit has been made available to the public and could be used for attacks. Patch name: 345c9a50ab07018f1b4439776bad78a0d40778ec. To fix this issue, it is recommended to deploy a patch.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| BYVoid | OpenCC | 1.1.0, 1.1.1, 1.1.2, 1.1.3, 1.1.4, 1.1.5, 1.1.6, 1.1.7, 1.1.8, 1.1.9 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | opencc | 1.1.9+ds1-4 | — |
| Debian 13 | opencc | 1.1.9+ds1-1+deb13u1 | — |
| Debian 12 | opencc | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | opencc | 1.1.9+ds1-2ubuntu0.1 | USN-7972-1 |
| Ubuntu 24.04 LTS | opencc | 1.1.7+ds1-1ubuntu0.1 | USN-7972-1 |
| Ubuntu 22.04 LTS | opencc | 1.1.3+ds1-3ubuntu3.1 | USN-7972-1 |
| Ubuntu 16.04 LTS | opencc | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | opencc | 1.0.5+git20190530-1ubuntu0.1~esm1 | USN-7972-2 |
| Ubuntu Pro 18.04 LTS | opencc | 1.0.4-5ubuntu0.1~esm1 | USN-7972-2 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | opencc | 1.2.0-1.1 | openSUSE-SU-2026:10102-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | opencc | 1.2.0-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | opencc | No fix yet | — |
| Azure Linux 2 (CBL-Mariner) | opencc | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| npm | opencc | < 1.2.0 | 1.2.0 | GHSA-5pr6-crvp-2j9f |
Advisories 3
- USN-7972-2 opencc vulnerability Ubuntu Security Notices (USN) · May 26, 2026
- USN-7972-1 opencc vulnerability Ubuntu Security Notices (USN) · Apr 27, 2026
- openSUSE-SU-2026:10102-1 libopencc1_2-1.2.0-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
References
- VDB-341708 | BYVoid OpenCC MaxMatchSegmentation.cpp MaxMatchSegmentation heap-based overflow vdb-entry technical-description
- VDB-341708 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- Submit #733347 | BYVoid OpenCC ver.1.1.9 and master-branch Heap-based Buffer Overflow third-party-advisory
- https://github.com/BYVoid/OpenCC/issues/997 issue-tracking
- https://github.com/BYVoid/OpenCC/pull/1005 issue-tracking
- https://github.com/oneafter/1222/blob/main/repro exploit
- https://github.com/BYVoid/OpenCC/commit/345c9a50ab07018f1b4439776bad78a0d40778ec patch
- https://github.com/BYVoid/OpenCC/ product