Description
The ucnv_UTF8FromUTF8 function in ucnv_u8.cpp in International Components for Unicode (ICU) for C/C++ through 60.1 mishandles ucnv_convertEx calls for UTF-8 to UTF-8 conversion, which allows remote attackers to cause a denial of service (stack-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted string, as demonstrated by ZNC.
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.
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
| SLES 12 SP2 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-2, SUSE-SU-2018:1401-1 |
| SLES 12 SP1 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
| SLES 12 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
| SLES 11 SP4 | icu | 4.0-47.6.1 | SUSE-SU-2018:1602-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP3 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
| SLES for SAP 12 SP2 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
| SLES for SAP 12 SP1 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
| SLES for SAP 11 SP4 | icu | 4.0-47.6.1 | SUSE-SU-2018:1602-1 |
| SUSE OpenStack Cloud 7 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
| SUSE Enterprise Storage 4 | icu | 52.1-8.7.1 | SUSE-SU-2018:1401-1 |
Advisories 4
- SUSE-SU-2018:1602-1 Security update for icu SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1401-1 Security update for icu SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1401-2 Security update for icu SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2025-1660 Oracle Utilities: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 28, 2025
References
- https://ssl.icu-project.org/trac/ticket/13490
- https://ssl.icu-project.org/trac/changeset/40714
- https://github.com/znc/znc/issues/1459
- https://ssl.icu-project.org/trac/attachment/ticket/13490/poc.cpp
- https://ssl.icu-project.org/trac/ticket/13510
- https://ssl.icu-project.org/trac/changeset/40715
- https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html