# CVE-2020-27787: upx-ucl: A Segmentaation fault was found in UPX in invert_pt_dynamic() function in p_lx_elf.cpp

CVE-2020-27787 is fixed in upx-ucl on 1 platform, first by DEBIAN-CVE-2020-27787, released August 18, 2022. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-27787
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0041
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 18, 2022

## Description

A Segmentaation fault was found in UPX in invert_pt_dynamic() function in p_lx_elf.cpp. An attacker with a crafted input file allows invalid memory address access that could lead to a denial of service.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | upx-ucl Debian 13.5 (trixie) | 3.96-1 | [DEBIAN-CVE-2020-27787](https://patchblox.com/security/data/fix/linux/debian-cve-2020-27787.md) | Aug 18, 2022 |
| Linux | upx-ucl Debian 14 | 3.96-1 | [DEBIAN-CVE-2020-27787](https://patchblox.com/security/data/fix/linux/debian-cve-2020-27787.md) | Aug 18, 2022 |

---

Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.