CVE-2018-1139: canonical ubuntu_linux Improper Input Validation
Vulnerability summary
CVE-2018-1139 is a high (CVSS 8.1) Improper Input Validation vulnerability in canonical ubuntu_linux. EPSS estimates a 3.10% chance of exploitation in the next 30 days, higher than 87.7% of scored vulnerabilities.
Not severe (CVSS 5.4, adjacent network); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 6 · Related 3Timeline
- 22-08-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
A flaw was found in the way samba before 4.7.9 and 4.8.4 allowed the use of weak NTLMv1 authentication even when NTLMv1 was explicitly disabled. A man-in-the-middle attacker could use this flaw to read the credential and other details passed between the samba server and client.
CVSS metrics
8 scores · 5 sources · 3 versions- OSV · AlpineEcosystem advisory · calculated8.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated8.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST5.4MediumCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- OSV · UbuntuEcosystem advisory · calculated8.1HighCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HDiffers
EPSS trend
Probability
3.10%
Chance of exploitation in the next 30 days
Percentile
88%
Versus all other CVEs
30-day change
No change 0.00 pp
From 3.10% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-20Improper Input ValidationThe product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
- CWE-522Insufficiently Protected CredentialsThe product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.
Affected systems
Known conditions: adjacent network, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Redhat3 products
Alpine1 product
- samba≥ 4.7.0, < 4.8.4-r0 | ≥ 4.7.0, < 4.7.6-r1
Canonical1 product
- ubuntu_linuxEOL14.04 | 16.04 | 18.04
Debian1 product
- samba< 2:4.8.4+dfsg-1
Samba1 product
- samba≥ 4.7.0, < 4.7.9 | ≥ 4.8.0, < 4.8.4
The samba team1 product
- samba< 4.7.9 | < 4.8.4
Ubuntu1 product
- samba< 2:4.7.6+dfsg~ubuntu-0ubuntu2.2
7 vendors · 9 products
References
14 links- bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-1139X Refsource CONFIRMIssue TrackingThird Party Advisory
