CVE-2020-27799
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX...
CVE-2020-27799 is a high vulnerability (CVSS 7.8) in Upx, published August 25, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.33%, the 26th percentile. Fixed in upx 4.0.0-r0.
- Severity
- 7.8 HighCVSS 3.1, NVD
- Exploit chance
- 0.33%EPSS, 26th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
4.0.0-r0upx +15 more
Description
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h 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
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
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 6 moreShow less
| Package | Affected | Fixed |
|---|---|---|
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 |
What each source reports
NVD Score used
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
CVE-2020-27799- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-119, CWE-125
- Updated
- 2026-11-02
CVE ListNo score
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
CVE-2020-27799- Weakness
- CWE-119
- Updated
- 2026-11-02
EUVDEUVD-2020-20301No score
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
EUVD-2020-20301- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-mj66-hgqf-6qqw
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX...
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
GHSA-mj66-hgqf-6qqw- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-119, CWE-125
- Updated
- 2026-11-02
OSVALPINE-CVE-2020-27799
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
ALPINE-CVE-2020-27799- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
OSVBELL-CVE-2020-27799
CVE-2020-27799 does not affect BellSoft software
- Record
BELL-CVE-2020-27799- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSV
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
CVE-2020-27799- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2020-27799
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
DEBIAN-CVE-2020-27799- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2020-27799
A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.
- Record
UBUNTU-CVE-2020-27799- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| 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.
References
github.com/upx/upx/issues/391
nvd.nist.gov/vuln/detail/CVE-2020-27799
security.alpinelinux.org/vuln/CVE-2020-27799
docs.bell-sw.com/security/cves/CVE-2020-27799
security-tracker.debian.org/tracker/CVE-2020-27799
ubuntu.com/security/CVE-2020-27799
cve.org/CVERecord?id=CVE-2020-27799