CVE-2020-27798
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX...
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
CVE-2020-27798- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-119, CWE-763
- Updated
- 2026-11-02
CVE List No score
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
CVE-2020-27798- Weakness
- CWE-119
- Updated
- 2026-11-02
EUVDEUVD-2020-20300 No score
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
EUVD-2020-20300- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-gqpc-4qr8-j9g3
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX...
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
GHSA-gqpc-4qr8-j9g3- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-119, CWE-763
- Updated
- 2026-11-02
OSVALPINE-CVE-2020-27798
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
ALPINE-CVE-2020-27798- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
OSVBELL-CVE-2020-27798
CVE-2020-27798 does not affect BellSoft software
- Record
BELL-CVE-2020-27798- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSV
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
CVE-2020-27798- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2020-27798
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
DEBIAN-CVE-2020-27798- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2020-27798
An invalid memory address reference was discovered in the adjABS function in p_lx_elf.cpp in UPX 4.0.0 via a crafted Mach-O file.
- Record
UBUNTU-CVE-2020-27798- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
upxAlpine:v3.17 |
before 4.0.0-r0 | 4.0.0-r0 |
upxAlpine:v3.18 |
before 4.0.0-r0 | 4.0.0-r0 |
upxAlpine:v3.19 |
before 4.0.0-r0 | 4.0.0-r0 |
upxAlpine:v3.20 |
before 4.0.0-r0 | 4.0.0-r0 |
upxAlpine:v3.21 |
before 4.0.0-r0 | 4.0.0-r0 |
upxAlpine:v3.22 |
before 4.0.0-r0 | 4.0.0-r0 |
upxAlpine:v3.23 |
before 4.0.0-r0 | 4.0.0-r0 |
upxAlpine:v3.24 |
before 4.0.0-r0 | 4.0.0-r0 |
upx-uclDebian:13 |
before 4.2.2-1 | 4.2.2-1 |
upx-uclDebian:14 |
before 4.2.2-1 | 4.2.2-1 |
Show 8 moreShow less
| Package | Affected | Fixed |
|---|---|---|
upx-uclUbuntu:16.04:LTS |
All versions, plus listed versions 3.91-1 |
None known |
upx-uclUbuntu:18.04:LTS |
All versions, plus listed versions 3.94-23.94-33.94-4 |
None known |
upx-uclUbuntu:20.04:LTS |
All versions, plus listed versions 3.95-23.95-2build1 |
None known |
upx-uclUbuntu:22.04:LTS |
All versions, plus listed versions 3.96-23.96-3 |
None known |
upx-uclUbuntu:24.04:LTS |
All versions, plus listed versions 3.96-34.2.2-3 |
None known |
upx-uclUbuntu:25.10 |
All versions, plus listed versions 4.2.4-14.2.4-1.1 |
None known |
upx-uclUbuntu:26.10 |
All versions, plus listed versions 4.2.4-1.1build1 |
None known |
upx-uclUbuntu:26.04:LTS |
All versions, plus listed versions 4.2.4-1.14.2.4-1.1build1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, aliases, references | OSV | |
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-27798 is a medium vulnerability (CVSS 5.5) in Upx, published August 25, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.29%, the 21st percentile. Fixed in upx 4.0.0-r0.
References
github.com/upx/upx/issues/396
nvd.nist.gov/vuln/detail/CVE-2020-27798
security.alpinelinux.org/vuln/CVE-2020-27798
docs.bell-sw.com/security/cves/CVE-2020-27798
security-tracker.debian.org/tracker/CVE-2020-27798
ubuntu.com/security/CVE-2020-27798
cve.org/CVERecord?id=CVE-2020-27798