MIT Kerberos 5 (aka krb5) 1.8.x through 1.8.3 does not reject RC4 key-derivation…
Priority LOW 32CWE-310Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · Low
- Fix status
- Fixed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat.
Summary
MIT Kerberos 5 (aka krb5) 1.8.x through 1.8.3 does not reject RC4 key-derivation checksums, which might allow remote authenticated users to forge a (1) AD-SIGNEDPATH or (2) AD-KDC-ISSUED signature, and possibly gain privileges, by leveraging the small key space that results from certain one-byte stream-cipher operations.
Why it matters now
EPSS 0.01916 79th percentileScored 2026-11-07
Fix Fixed Red Hat: 1 advisory
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mit:kerberos_5:1.8:*:*:*:*:*:*:* | 1.8 | Vulnerable | moos-ivp |
| cpe:2.3:a:mit:kerberos_5:1.8.1:*:*:*:*:*:*:* | 1.8.1 | Vulnerable | moos-ivp |
| cpe:2.3:a:mit:kerberos_5:1.8.2:*:*:*:*:*:*:* | 1.8.2 | Vulnerable | moos-ivp |
| cpe:2.3:a:mit:kerberos_5:1.8.3:*:*:*:*:*:*:* | 1.8.3 | Vulnerable | moos-ivp |
- cpe:2.3:a:mit:kerberos_5:1.8:*:*:*:*:*:*:* Versions 1.8 Vulnerable ·moos-ivp
- cpe:2.3:a:mit:kerberos_5:1.8.1:*:*:*:*:*:*:* Versions 1.8.1 Vulnerable ·moos-ivp
- cpe:2.3:a:mit:kerberos_5:1.8.2:*:*:*:*:*:*:* Versions 1.8.2 Vulnerable ·moos-ivp
- cpe:2.3:a:mit:kerberos_5:1.8.3:*:*:*:*:*:*:* Versions 1.8.3 Vulnerable ·moos-ivp
Remediation
Red Hat 1 advisory
- RHSA-2010:0925 Released 2010-11-30 · Red Hat rating Importantkrb5 security and bug fix update
- Red Hat Enterprise Linux Desktop (v. 6) krb5-1.8.2-3.el6_0.3, krb5-libs-1.8.2-3.el6_0.3, krb5-pkinit-openssl-1.8.2-3.el6_0.3 +1
- Red Hat Enterprise Linux Desktop Optional (v. 6) krb5-1.8.2-3.el6_0.3, krb5-devel-1.8.2-3.el6_0.3, krb5-server-1.8.2-3.el6_0.3 +1
- Red Hat Enterprise Linux HPC Node (v. 6) krb5-1.8.2-3.el6_0.3, krb5-libs-1.8.2-3.el6_0.3
- Red Hat Enterprise Linux HPC Node Optional (v. 6) krb5-1.8.2-3.el6_0.3, krb5-devel-1.8.2-3.el6_0.3, krb5-pkinit-openssl-1.8.2-3.el6_0.3 +3
- Red Hat Enterprise Linux Server (v. 6) krb5-1.8.2-3.el6_0.3, krb5-devel-1.8.2-3.el6_0.3, krb5-devel-1.8.2-3.el6_0.3.ppc +7
- Red Hat Enterprise Linux Workstation (v. 6) krb5-1.8.2-3.el6_0.3, krb5-devel-1.8.2-3.el6_0.3, krb5-libs-1.8.2-3.el6_0.3 +4
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux Desktop (v. 6) | Fixed | RHSA-2010:0925 |
| Red Hat Enterprise Linux Desktop Optional (v. 6) | Fixed | RHSA-2010:0925 |
| Red Hat Enterprise Linux HPC Node (v. 6) | Fixed | RHSA-2010:0925 |
| Red Hat Enterprise Linux HPC Node Optional (v. 6) | Fixed | RHSA-2010:0925 |
| Red Hat Enterprise Linux Server (v. 6) | Fixed | RHSA-2010:0925 |
| Red Hat Enterprise Linux Workstation (v. 6) | Fixed | RHSA-2010:0925 |
Not affected: 1 product
- Red Hat Enterprise Linux 5
Timeline
- 2026-10-02 Threatist record created from CVE-2010-4020
- 2026-10-03 Alias added: GHSA-27hw-qqm8-6prm
References
Advisory 9
Other 8
- ADV-2010-3094
- http://kb.vmware.com/kb/1035108
- ADV-2010-3118
- http://www.vmware.com/security/advisories/VMSA-2011-0007.html
- ADV-2010-3095
- [security-announce] 20110428 VMSA-2011-0007 VMware ESXi and ESX Denial of Service and third party updates for Likewise components and ESX Service Console
- 69608
- http://support.apple.com/kb/HT4581
More moos-ivp Kerberos 5 vulnerabilities
- TI-2024-17421 Kerberos 5 (aka krb5) 1.21.2 contains a memory leak vulnerability in /krb5/src/lib/gssapi/krb5/k5sealv3.c. CVSS 3.1HIGH 7.5
- TI-2001-00539 Buffer overflow in BSD-based telnetd telnet daemon on various operating systems allows… CVSS 2.0HIGH 10.0
- TI-2026-29130 NULL pointer dereference in moos-ivp Kerberos 5 CVSS 3.1HIGH 7.5
- TI-2007-00929 The telnet daemon (telnetd) in MIT krb5 before 1.6.1 allows remote attackers to bypass… CVSS 2.0HIGH 10.0
- TI-2011-00268 The process_chpw_request function in schpw.c in the password-changing functionality in… CVSS 2.0HIGH 10.0
- TI-2001-00245 Buffer overflows in BSD-based FTP servers allows remote attackers to execute arbitrary… CVSS 2.0HIGH 10.0
Sources
- CVE-2010-4020 · CVE Program
- CVE-2010-4020 · NVD
- FIRST EPSS
- GHSA-27hw-qqm8-6prm · GitHub Advisory Database · CC BY 4.0
- CVE-2010-4020 · Red Hat security data · CC BY 4.0
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