CVE-2026-1858
wget2 Improper Certificate Validation
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
wget2 Improper Certificate Validation
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.
- Record
CVE-2026-1858- CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
EUVDEUVD-2026-26285
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.
- Record
EUVD-2026-26285- CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-9h5h-4q77-cphm
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If...
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.
- Record
GHSA-9h5h-4q77-cphm- CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
NVD
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.
- Record
CVE-2026-1858- CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-1858
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.
- Record
DEBIAN-CVE-2026-1858- CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-1858
wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.
- Record
UBUNTU-CVE-2026-1858- CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
wget2Debian:12 |
All versions, plus listed versions 1.99.1-2.22.1.0-12.1.0-22.1.0-2.12.1.0-2.1~exp1 Show 9 moreShow less2.1.0-32.1.0-42.1.0-52.2.0+ds-12.2.0+ds-1~exp12.2.0+ds-1~exp22.2.0+ds-1~exp32.2.0+ds-22.2.0+ds-3 |
None known |
wget2Debian:13 |
All versions, plus listed versions 2.2.0+ds-12.2.0+ds-1+deb13u12.2.0+ds-22.2.0+ds-3 |
None known |
wget2Debian:14 |
All versions, plus listed versions 2.2.0+ds-12.2.0+ds-22.2.0+ds-3 |
None known |
wget2Ubuntu:18.04:LTS |
All versions, plus listed versions 0.0.20170806-1 |
None known |
wget2Ubuntu:20.04:LTS |
All versions, plus listed versions 1.99.1-21.99.1-2.1 |
None known |
wget2Ubuntu:22.04:LTS |
All versions, plus listed versions 1.99.1-2.2 |
None known |
wget2Ubuntu:24.04:LTS |
All versions, plus listed versions 1.99.1-2.22.1.0-22.1.0-2.1build12.1.0-2.1build2 |
None known |
wget2Ubuntu:25.10 |
All versions, plus listed versions 2.2.0+ds-1 |
None known |
wget2Ubuntu:26.10 |
All versions, plus listed versions 2.2.0+ds-3build1 |
None known |
wget2Ubuntu:26.04:LTS |
All versions, plus listed versions 2.2.0+ds-12.2.0+ds-22.2.0+ds-32.2.0+ds-3build1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-1858 is a medium vulnerability (CVSS 4.8) in Gnu Wget2, published April 29, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.15%, the 4th percentile. No source names a fixed version.