CVE-2026-91142: Cockpit: cockpit: unauthorized modification of login records via integer overflow
Vulnerability summary
CVE-2026-91142 is a low (CVSS 3.6) Out-of-bounds Write vulnerability in cockpit. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.7% of scored vulnerabilities.
Not severe (CVSS 3.6, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 18-09-2026PublishedVulnerability first disclosed.
- 16-10-2026Last modifiedVulnerability information updated.
Description
A flaw was found in Cockpit. An authenticated local user with a large user identifier (UID) can cause unauthorized modification and disclosure of login records. On 32-bit systems, an integer overflow during session accounting allows the user's login process to read or overwrite the legacy log entries of other accounts.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated3.6LowCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
- OSV · DebianEcosystem advisory · calculated3.6LowCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
- NVDNIST3.6LowCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS trend
Probability
0.12%
Chance of exploitation in the next 30 days
Percentile
2%
Versus all other CVEs
30-day change
Decrease -0.01 pp
From 0.13% 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-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
- CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Debian1 product
- cockpitAll versions (No fix recorded) | < 368-1
Ubuntu1 product
- cockpitAll versions (No fix recorded)
2 vendors · 2 products
