SB20261109128 - Fedora 44 update for ruby
Published: November 9, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Improper access control (CVE-ID: CVE-2026-41316)
CWE-ID: CWE-284 - Improper Access Control
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to improper access control in ERB#def_module, ERB#def_method, and ERB#def_class when deserializing untrusted data with Marshal.load. A remote attacker can supply crafted serialized data to bypass the @_init guard and execute arbitrary code.
Exploitation requires both erb and activesupport to be loaded.
2) Inefficient Algorithmic Complexity (CVE-ID: CVE-2026-42245)
CWE-ID: CWE-407 - Inefficient Algorithmic Complexity
CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows an unauthenticated remote attacker to exhaust a net-imap client's CPU and cause a denial of service.
The vulnerability exists due to quadratic processing in Net::IMAP::ResponseReader when repeated scans of a growing response buffer process many string literals. An unauthenticated remote attacker can send crafted responses from a hostile IMAP server to a connected client, causing excessive CPU consumption even below the default max_response_size limit.
3) Command injection (CVE-ID: CVE-2026-42258)
CWE-ID: CWE-77 - Command injection
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows an unprivileged local attacker to inject IMAP commands and delete mailboxes when a user triggers a vulnerable application command.
The vulnerability exists due to missing validation of Symbol arguments in net-imap when applications pass user-controlled input as Symbols to IMAP commands. An unprivileged local attacker can include CRLF sequences in a Symbol to terminate the original command and append a mailbox deletion command.
4) Not Failing Securely ('Failing Open') (CVE-ID: CVE-2026-42246)
CWE-ID: CWE-636 - Not Failing Securely (\'Failing Open\')
CVSSv4: 7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows an unauthenticated network attacker to bypass TLS and expose sensitive information transmitted by an IMAP client.
The vulnerability exists due to net-imap accepting an early success response during a STARTTLS upgrade of a plaintext connection without ensuring TLS is established. An unauthenticated network attacker can intercept the connection and inject a predictably tagged response before the command finishes, leaving subsequent traffic unencrypted when the client does not explicitly verify TLS.
5) Command injection (CVE-ID: CVE-2026-47240)
CWE-ID: CWE-77 - Command injection
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows an unprivileged local attacker to inject arbitrary IMAP commands into an application's session and delete mailboxes.
The vulnerability exists due to net-imap accepting non-synchronizing literals in raw arguments without verifying server support. An unprivileged local attacker can supply input that an application passes unvalidated to affected arguments, causing servers lacking literal support that continue after malformed commands to execute embedded commands.
Remediation
Install update from vendor's website.