Upstream information

CVE-2025-61770 at MITRE

Description

Rack is a modular Ruby web server interface. In versions prior to 2.2.19, 3.1.17, and 3.2.2, `Rack::Multipart::Parser` buffers the entire multipart preamble (bytes before the first boundary) in memory without any size limit. A client can send a large preamble followed by a valid boundary, causing significant memory use and potential process termination due to out-of-memory (OOM) conditions. Remote attackers can trigger large transient memory spikes by including a long preamble in multipart/form-data requests. The impact scales with allowed request sizes and concurrency, potentially causing worker crashes or severe slowdown due to garbage collection. Versions 2.2.19, 3.1.17, and 3.2.2 enforce a preamble size limit (e.g., 16 KiB) or discard preamble data entirely. Workarounds include limiting total request body size at the proxy or web server level and monitoring memory and set per-process limits to prevent OOM conditions.

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having important severity.

CVSS v3 Scores
CVSS detail CNA (GitHub) SUSE
Base Score 7.5 7.5
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network Network
Attack Complexity Low Low
Privileges Required None None
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact None None
Integrity Impact None None
Availability Impact High High
CVSSv3 Version 3.1 3.1
CVSS v4 Scores
CVSS detail SUSE
Base Score 8.7
Vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Attack Vector Network
Attack Complexity Low
Attack Requirements None
Privileges Required None
User Interaction None
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact None
Vulnerable System Availability Impact High
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
CVSSv4 Version 4.0
SUSE Bugzilla entry: 1251245 [NEW]

No SUSE Security Announcements cross referenced.

Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise High Availability Extension 15 SP6 rubygem-rack Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 rubygem-rack Affected
openSUSE Leap 15.6 rubygem-rack Affected
openSUSE Leap 15.6 rubygem-rack-1_6 Not affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Availability Extension 15 SP3 rubygem-rack Affected
SUSE Linux Enterprise High Availability Extension 15 SP4 rubygem-rack Affected
SUSE Linux Enterprise High Availability Extension 15 SP5 rubygem-rack Affected
Products past their end of life and not receiving proactive updates anymore.
SUSE Linux Enterprise High Availability Extension 15 rubygem-rack Affected
SUSE Linux Enterprise High Availability Extension 15 SP1 rubygem-rack Affected
SUSE Linux Enterprise High Availability Extension 15 SP2 rubygem-rack Affected
openSUSE Leap 15.3 rubygem-rack Affected
openSUSE Leap 15.3 rubygem-rack-1_6 Not affected
openSUSE Leap 15.4 rubygem-rack Affected
openSUSE Leap 15.4 rubygem-rack-1_6 Not affected
openSUSE Leap 15.5 rubygem-rack Affected
openSUSE Leap 15.5 rubygem-rack-1_6 Not affected

SUSE Timeline for this CVE

CVE page created: Tue Oct 7 18:02:35 2025
CVE page last modified: Tue Oct 7 22:28:23 2025