Out-of-bounds Read in Samba
CVE-2020-27840
A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.038 (89.7th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 89.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.038 · newest: 0.038 · change: 0.000
Affected products
- Samba
- Debian Linux — versions 9.0, 10.0
- Fedoraproject Fedora — versions 32, 33, 34
- Samba — versions samba 4.14.1, samba 4.13.6, samba 4.12.13
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security.netapp.com/advisory/ntap-20210326-0007/ (Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.debian.org/debian-lts-announce/2021/03/msg00036.html (mailing-list, Mailing List, Third Party Advisory)
- www.debian.org/security/2021/dsa-4884 (vendor-advisory, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
- www.samba.org/samba/security/CVE-2020-27840.html (Vendor Advisory)
- security.gentoo.org/glsa/202105-22 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-27840?
- CVE-2020-27840 is a high-severity vulnerability in Samba, classified under Out-of-bounds Read. CVSS score: 7.5/10. Published 2021-05-12.
- How severe is CVE-2020-27840?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2020-27840 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.