Description
An assertion abort was found in upx MemBuffer::alloc() in mem.cpp, in version UPX 4.0.0. The flow allows attackers to cause a denial of service (abort) via a crafted file.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | upx | upx 4.0 | — |
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 | upx-ucl | 4.2.2-1 | — |
| Debian 13 | upx-ucl | 4.2.2-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | upx-ucl | No fix yet | — |
| Ubuntu 26.04 LTS | upx-ucl | No fix yet | — |
| Ubuntu 25.10 | upx-ucl | No fix yet | — |
| Ubuntu 24.04 LTS | upx-ucl | No fix yet | — |
| Ubuntu 22.04 LTS | upx-ucl | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | upx-ucl | No fix yet | — |
| Ubuntu 18.04 LTS | upx-ucl | No fix yet | — |
| Ubuntu 16.04 LTS | upx-ucl | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SUSE Package Hub 15 SP4 | upx | 4.0.2-bp154.4.6.1 | openSUSE-SU-2023:0088-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.4 | upx | 4.0.2-bp154.4.6.1 | openSUSE-SU-2023:0088-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | upx | 4.0.0-r0 | — |
| Alpine v3.23 | upx | 4.0.0-r0 | — |
| Alpine v3.22 | upx | 4.0.0-r0 | — |
| Alpine v3.21 | upx | 4.0.0-r0 | — |
| Alpine v3.20 | upx | 4.0.0-r0 | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | upx | 4.0.0-r0 | — |
| Alpine v3.18 | upx | 4.0.0-r0 | — |
| Alpine v3.17 | upx | 4.0.0-r0 | — |
Advisories 1
- openSUSE-SU-2023:0088-1 Security update for upx SUSE / openSUSE Security Updates · May 7, 2025